Dutch Cold Case Murder Solved After 8000 People Gave Their DNA

sciencewatcher writes "A 1999 cold case rape and murder in The Netherlands has been solved. Dutch police asked 8000+ men living within 5 kilometers of the crime scene to volunteer their DNA so that the murderer could be traced through (close or distant) family members sharing part of this DNA. As it turned out, the man now in custody turned in his own DNA, resulting in a 100% match. The request of the police was discussed here on Slashdot in September. The percentage of people participating was closing in on 90%; in the midsize town of the victim it was 96%."

Comments

Interesting

[MyLongNickName]

It is interesting to see the different attitudes toward volunteering information to the government. If NYC asked something like this, it would be an outrage and participation would be roughly 1% if it moved forward at all.

Re:Interesting

[Anonymous Coward]

Lucky to get 1% before the ACLU (Or some other group) files suit to block

Re:Interesting

[Anonymous Coward]

"volunteering"...?

"You can volunteer your DNA to eliminate yourself as a suspect, and eliminate the need of SWAT kicking down your door to get the DNA."

Re:Interesting

[Anonymous Coward]

I don't know about their government but what I do know is that our government would store that DNA data forever. Not only that but they would share this DNA data with anyone, possibly including Insurance companies, and private corporations. Finally the last straw is that even if they don't just give the data away they will not take any consideration to secure the data.

This is why we don't want the NYC government getting the data.

Re:Interesting

[91degrees]

This is curious though. Europe does have a much stronger tradition of personal privacy, at least in the sense of things like stronger data protection laws. I wonder if this legal protection means they're less likely to have concerns about this.

Re:Interesting

[citizenr]

I don't know about their government but what I do know is that our government would store that DNA data forever.

This is the second such case. They promised to destroy samples after first one ended - of course they lied :). People still wanted the second one. People like to be sheep

Re:Interesting

[poetmatt]

actually, no - it's interesting to see what actual happens, because the question is - how/why does this DNA match actually matter?

It's nearly as impossible to associate DNA at a crime scene with an individual being actually involved without further proof - otherwise this is in the same category as trying to assign an IP address to an individual.

Re:Interesting

[Anonymous Coward]

The DNA data could only be used for this particular investigation. It will not be added to the national DNA database that exists for suspects.
Also, the match that has been found will considered to be circumstantial evidence, but is sufficient for an arrest warrant. Note that a confession is also merely circumstantial evidence.

Re:Interesting

[Joce640k]

Yep. Some governments in the world would actually not store the DNA forever, "just in case".

Unthinkable, I know. But it's true.

Re:Interesting

[gatesstillborg]

Yeah, and then you know they'd have you on the books forever!

Re:Interesting

[readin]

I find this method seriously scary due to the probability of a false positive. I mean, suppose you have a system that only fails once in a million times and the killer has already left the country. You ask the two million people in the metropolitan area to submit DNA. You get on average two matches. One doesn't have an alibi. You take him to trial and tell the jury that he not only doesn't have an alibi, he had a 1 in a million DNA match. It sounds pretty convincing. It is very possible the jury won't have the understanding of statistics to ask "was this a sweep or did you only test a couple of likely suspects?" Nor is it likely that the information will be volunteered by the court.

Re:Interesting

[interkin3tic]

I would hope so. It could be that one "success" of volunteer submissions could pave the way to some lawmaker suggesting it be "encouraged." Then outright mandatory. I'd rather err on the side of having murders and rapes go unsolved, rather than err on the side of police having everyone's DNA sequences.

Re:Interesting

[Pieroxy]

I don't think you understand DNA very well. Unless you have an identical twin, you're the only one with your DNA.

Now, when they do a "quick scan" like the one we're talking about here, they don't compare everything. But I would think that when they get a match (say 2 on 2M people) they run a full scan. Maybe I'm wrong. And maybe you don't need it because it is probable that when the match is done the suspect confess. End of story.

Re:Interesting

[Tuoqui]

Well you have to remember birthday paradox...

In a room of about 20 people you have a 50/50 chance of having the same birthday as someone else in the room. What they're doing here is taking one sample and comparing it to hundreds or thousands of men.

I've been lead to believe that birthday paradox also applies to DNA too... So if you take a sample size of thousands or so presumably unrelated people you might find people who match in such a way that it would be acceptable evidence in a court of law.

Someone smarter than me can do the math but 1:1,000,000 chance vs 3,000 Samples ... How many are likely to come up close enough to prosecute?

Re:Interesting

[westlake]

It is interesting to see the different attitudes toward volunteering information to the government. If NYC asked something like this, it would be an outrage and participation would be roughly 1% if it moved forward at all.

Have you any evidence to support that assertion or do you simply think that these are the words the geek wants to hear?

Re:Interesting

[Anonymous Coward]

Except the birthday paradox doesn't apply. You aren't trying to figure out if a group exists where some set of two people have similar DNA. You instead have a fixed set of DNA that you are comparing to each and every other person in the group. Big difference.

Re:Interesting

[Xenna]

Agreed, that's interesting.
Let's see what happens.

In this case it's actually a bit of a pity that the suspect volunteered to give his DNA. It would've been more interesting if they'd found him through DNA supplied by his relatives.

Re:Interesting

[Anonymous Coward]

The would be cool if they sequenced all the dna for comparison, but they don't. They look for specific markers that can actually be alike in unrelated people. A small chance, but not zero.

Re:Interesting

[Vintermann]

A confession should not be the end of the story. An instructive case in the news these days is the story of Sture Bergwall, better known under his serial killer name Thomas Quick. It turns out he likely didn't kill a single person - he was just a disturbed drug addict who made up stories (mostly under the influence of strong sedatives and "repressed memory therapy") to fit unsolved cases. They glossed over his inaccuracies, contradictions and the total lack of evidence in case after case, year after year.

(An interesting bit is that Bergwall's defender was the lawyer/politician Claes Borgstöm, who's currently infamous for pursuing Julian Assange. If he had done any due dilligence at all, he must have suspected something was amiss. You got to wonder if there was something in his ideology which caused that gross failure.)

A lot of people, who aren't so smart and are aware of it, tend to be totally dominated by supposedly scienfific authorities. If the authority says it's absolutely certain you did it, they would rather doubt their own recall than the authority.

Re:Interesting

[yabos]

Then if they are really interested in you, they can get a warrant. Stand up for your rights.

Re:Interesting

[Pete (big-pete)]

In a room of about 20 people you have a 50/50 chance of having the same birthday as someone else in the room.

No, no, no, no, no! In a room of about 20 people there is a 50/50 chance of having two people with the same birthday. This is absolutely different of you having the same birthday as someone else, which is about 5.5% chance.

-- Pete.

Re:Interesting

[Synerg1y]

It's interesting to see this guy come forward, you can google dna testing and figure out what's going on. If he was indeed the killer he could've voluntarily declined, like I'm sure some people did. DNA testing is also known for being wrong, so I wouldn't be surprised to see the Dutch government recant their solution sometime in the near future, this guy based on the article's description doesn't sound like your typically perp.

Re:Interesting

[kelemvor4]

It is interesting to see the different attitudes toward volunteering information to the government. If NYC asked something like this, it would be an outrage and participation would be roughly 1% if it moved forward at all.

I certainly wouldn't volunteer mine.

Re:Interesting

[jiriw]

No... People want to have a murder solved. There is a difference. And if you can't trust your government then you live in a very sorry nation indeed.

The hard part is voting the right people in to be your political leaders. Now I don't say everything is all shiny here in the Netherlands because it isn't. But at least we know we can vote every four years and have a choice of political parties to choose from who are actually -different-. And that an absolute majority is a herculean task to achieve so we always have coalitions. Which is good because it means politics has to care about minorities. So, next time you go to the voting box (if you actually do live in the Netherlands), do not vote for the party(/ies) that try to relax the privacy laws so you can actually put a little trust into the government for not randomly trying to fuck you up.

By the way, just in: nu.nl. The second, minute DNA test (which took 6 hours to perform) also identifies the suspect as the one matching the traces both on the victims body and the lighter found at the scene of the crime.

Re:Interesting

[SecurityGuy]

You are wrong. They don't sequence and compare your entire genome.

Re:Interesting

[nedlohs]

They don't do a "full scan", the marker matches is it. Crime scene samples are contaminated anyway so you aren't getting a "full scan" out of it in the first place.

In the case of "we suspect X due to this evidence, test his DNS for a match" then a match to enough markers would be very good evidence - it's very unlikely he would match by chance. But doing it the other way "compare all these samples against this one" gives you a much higher chance of a random match. 8000 isn't that high a number though - assuming they had a lot of markers. It's still a terrible way to use DNA evidence - and you can be pretty sure they won't tell the jury about the actual odds of a random match in a multi-sample comparison and instead just use the 1:1 match odds.

Re:Interesting

[operagost]

No government should be trusted. Ever. If you trust your government, you will be a sorry nation indeed.

Re:Interesting

[QuasiSteve]

It's interesting to see this guy come forward, you can google dna testing and figure out what's going on. If he was indeed the killer he could've voluntarily declined, like I'm sure some people did.

People did, both in this test, and the previous test. I don't think they've mentioned whether this suspect had also had a DNA sample taken the first time around.

Here's the thing about this second set of tests. They weren't specifically looking for a direct match with the perp (though that ending up being the case is, I'm sure, a boon) but rather for a match to a family member of the perp.

So assume the first time around he declined to let a DNA sample be taken, and gets to walk scott free.

But this second time around, his sons who actually knew the victim at the time, may or may not be tested against. Being the father of them, he could either take that risk and hope they did not get tested against... or also supply a sample to spare his sons the additional shame, guilt, etc. of effectively having ousted their very own father by virtue of the lab having a direct match.

That would be my guess as to any reason for coming forward, at least. Who knows, maybe he just started feeling guilty, grew a conscience, etc. and the above is unrelated.

Re:Interesting

[vertigovegan]

You should find it scary. The odds of a false positive are probably much higher.

The DNA database in the US has found matches between a black man and a white man if you point it at itself. They only look at about 12 spots and sometimes use just 9 to identify someone.

"903 pairs of profiles matching at nine or more loci in a database of about 220,000. ...State officials obtained a court order to prevent distribution of the results."

http://news.lawreader.com/2008/07/22/dna-match-between-two-men-raises-question-about-validity-of-dna-tests%E2%80%A6fbi-seeks-to-block-inquiry/
http://www.deathpenaltyinfo.org/accuracy-dna-matches-definitively-identify-suspects-questioned

Re:Interesting

[asmkm22]

Reminds me of a TED talk...

http://www.ted.com/talks/peter_donnelly_shows_how_stats_fool_juries.html

Re:Interesting

[meerling]

There are a lot of 'false positives' in the DNA testing industry. Human error, stupidity, desire to please the authorities, or for whatever reason it might be, it happens.
A few years back in the USA someone (I think it was a reporter) decided to test the accuracy of the DNA testing companies. They sent in samples as if from a criminal investigation that would NOT match. Almost all the companies returned 'matches'. That really throws into question the results of the companies, even though the science is solid.

The accused should get a 'second opinion' from a reputable testing facility that has been independently verified for accuracy. And by the way, it's many many times for likely that a false result will be a positive than a negative. (An inconclusive is yet another and different result from positive or negative.)

Re:Interesting

[magarity]

This is curious though. Europe does have a much stronger tradition of personal privacy, at least in the sense of things like stronger data protection laws. I wonder if this legal protection means they're less likely to have concerns about this.

Sure there's higher tradition of personal privacy *when companies are involved*.

Re:Interesting

[pe1rxq]

They did.
There were multiple family matches. (including his father and his son)
Why he also gave DNA himself is interesting though... was it due to social pressure, did he want to get caught, maybe he didn't believe they could really match it....

Re:Interesting

[dbet]

That's because NYC would keep your DNA on file forever, and use it to bust you for things that aren't even crimes, like protesting.

Re:Interesting

[Johann Lau]

if you can't trust your government then you live in a very sorry nation indeed.

Wow. In what nation do you live, pray tell? Did they achieve this remarkable success just by fooling you, or were you outright re-educated?

The hard part is voting the right people in to be your political leaders.

LOLNOPE.

The hard part is that you vote based on promises, and those people are not at all bound by that promise, or your vote. Once they're voted in they can do whatever, including the opposite of what they promised. While it's illegal to put up a fake vending machine (which promises X, but only gives you something else, or even nothing, after you inserted money), there are no such qualms with politicians, and certainly no laws, not to mention enforcement of them, regulating politicians and their false promises.

You can only trust *anything* it in so far as you can influence it, and/or in so far as it loves you. No such dice with governments usually. So unless your country radically differs from this, if you trust the government, you're being silly. And even if it does, even if *you* can trust *your* government, because it's really special that way, then the easiest way to loose that is to look down your nose at people who are making different experiences with theirs, and taking the fact that you're not raped and thrown away for granted.

Re:Interesting

[jc42]

We should be pointing out that, with stories like this, saying "100% match" does not mean that they tested 100% of his DNA, and it all matched. What it means is that they tested an unknown fraction of his DNA, probably much less that 1% of it, and that tiny portion matched.

Media reporting of statistical results like this are generally guilty of exaggerating the "percent match" by orders of magnitude. They may know that the testing wasn't of 100% of the evidence, and in such cases, phrasing such as what's in this summary is used knowing full well that it will be misinterpreted by most readers. (I almost typed "100% of readers" there. ;-) In many cases, the reporters have so little understanding of statistics and DNA testing that they probably thought that all the DNA was tested, and it all matched. They're just incompetent to report on the topic. But that doesn't prevent them from reporting, and their words get repeated with very rarely any questions about their accuracy.

Re:Interesting

[HeckRuler]

This and double this. A lot of people confess to things they didn't do. It's not just the mentally ill off their drugs. If the cops suspect you've done something they will grill you like it's their professional job. They'll claim any number of lies about what your future looks like, what evidence they have, and what the best course of action would be for you. You'll be faced with DECADES in prison vs a few years of probation because "you cooperated".

All that said, DNA test aren't the loose guesstimation that finger-print reading has been in the past. They have a false-positive rate, but I'm pretty sure they could just run it again. Scientific authorities are actually pretty authoritative. They're also usually not the ones in charge.

Re:Interesting

[Firethorn]

Tuoqui - Pete's post is accurate. You only need ~20 people for a 50% chance that two of those in the room have matching birthdays, but in this case we've already fixed 1 of them, thus the possiblitiy plumments down to 5.5%

Pete, I wonder - Given that DNA has a whole lot more than 366 possibilties, how many people do you need to have two that were born on the same day, for a properly randomized group of people?

It's not really in the article, but they've managed to get DNA testing science good enough that they can generally detect family lines. From what I've read, cousins can even provide clues. If a parent or child is tested, it's pretty slam dunk, grandparents, grandchildren, and cousins are more difficult, but still workable with a data set of 8k or so people. It can become complicated when you're looking at a somewhat closed breeding pool, US genetic lines are very different than some European countries. More diversified. On the other hand, you're less likely to get a parent if you simply check the city.

Though I think it's interesting that they only asked the men to be tested - finding a mother/daughter would be just as valuable if they weren't fairly convinced that the guy would get tested himself.

Re:Interesting

[jiriw]

The devil is in the details. I don't say you HAVE to trust your government, just that it's sorry IF you CAN'T trust the government. But then, maybe this is all because of cultural differences and we'll never agree.

Now, in what world would you live if you actually COULD trust the government to do good things and they would? Or if you knew that when they did wrong it could be amended just by a proper re-vote instead of having to implement drastic measures like carving the right to bear arms into a constitution which will fly out of the window anyway if a government really wants to implement evil... and in the mean time will inflict all kinds of harm to society. (Excuse me if I'm uninformed but I regularly read about all kinds of nasties happening over the pond, like public place mass murders, children having gun accidents, increased rates of crimes with lethal consequences etc. Here those things are... drastically less frequent.) Of course, it's your nation.. your peoples decisions. Not wanting to lecture here but please do allow me to find things odd, as you do about us.

Think about it.

Now, mod me into oblivion if you're a true patriot. I'm nothing of the sort. But I am someone willing to trust until someone shatters it... within common sense of course. I'm not that much willing to hand over advance fees to Nigerian princes.

Re:Interesting

[TWX]

The DNA data could only be used for this particular investigation. It will not be added to the national DNA database that exists for suspects.

BwhaHAHAHAHAHA!!!

Oh wait, you're serious?

Re:Interesting

[houghi]

I am a Siamese twin, you insensitive clod.

Re:Interesting

[poetmatt]

I don't think anyone will follow the case. Given that the article says

The decision to launch the dna appeal came after De Vries in May broadcast information about a Playboy cigarette lighter found in Vaatstra's bag which contains dna traces that match the traces found on the schoolgirl's body.

and that this is a tiny area (identified by only having 6600 people involved in the first place - where does 8k even come from?), this is why I want to know if this is a situation of:

"he was in the area at any random time prior"
or "he was directly responsible", as those are very different things. I'm not going to speculate but instead say that there is very little information at the moment.

I personally think that if someone murdered someone and was trying to stay free they would avoid volunteering their DNA at any costs. However, if you knew you were innocent and asked to submit your DNA in a country where gov't can ask for it, would you be as unwilling to donate DNA? I would assume the argument could go either way.

Re:Interesting

[Capt.DrumkenBum]

I'd rather err on the side of having murders and rapes go unsolved, rather than err on the side of police having everyone's DNA sequences.

Why? Not trolling, but it seems to me that if everyone's DNA were on record the crime rates would drop through the floor.
Maybe I feel this way because a good friend of mine was raped a few years ago, and if all DNA were recorded the asshole who did that to her would probably be rotting in jail right now.

Re:Interesting

[mariox19]

There is no end to the amount of crimes that could be prevented or solved if only we were ready to embrace draconian governmental invasions of our privacy and restrictions on our freedom of choice. Do you realize that if we only had laws forbidding women from traveling alone in public without being escorted by a male relative how many rapes we might prevent each year?

Re:Interesting

[TheRealGrogan]

I am very suspicious about this. Why would he submit a sample if he is the one who did it? This is probably all bollocks and the man is innocent.

I would never submit my DNA in that manner. If that made me the odd man out, implying guilt because I won't cooperate, so be it. If they go and take a sample by whatever means, it wouldn't be admissible anyway.

This is like a witch hunt.

Re:Interesting

[F.Ultra]

Since it was murder/rape I guess that the rapist left the dna in a place where only a person having had sex with the victim would leave it sort of...

Re:Interesting

[cayenne8]

This and double this. A lot of people confess to things they didn't do. It's not just the mentally ill off their drugs. If the cops suspect you've done something they will grill you like it's their professional job. They'll claim any number of lies about what your future looks like, what evidence they have, and what the best course of action would be for you. You'll be faced with DECADES in prison vs a few years of probation because "you cooperated".

First rule of thumb, never talk to the cops. Shut up...and lawyer up, this is ESPECIALLY true if you are innocent.

The police are not and never have been there to help you, they are there to try to solve a case and pin the rap on someone....hopefully the criminal, but often the innocent can get very damaged too if not downright wrongly convicted.

Anyone that talks to the cops is an idiot.....it is up to you to know your rights, and at least in the US, the one were you can SHUT up is about the most important one there is.

Re:Interesting

[plover]

No, you're missing how DNA testing works. One chromosome has millions of nucleotides in a unique sequence, but for Law Enforcement purposes, they don't want to fully sequence everyone's complete genome, because that takes many thousands of dollars and a very long time. Instead, they look at only a dozen or so points along the sequence, and if enough of them match, they go back and do a more thorough comparison of more points in the sequence.

The more closely you are related to the target DNA, the better your sequences match. So if your DNA was a close match to that found at a crime scene, the suspect might be your parents, your children, or your siblings. A more distant relative (a cousin, a grandparent) will have less of a match.

What they were trying to do in this town was to find someone who was distantly related to the suspect. Then they would check that family tree looking for cousins, uncles, brothers. Perhaps by testing that guy's uncle they would discover that he was the father of the suspect. That narrows down the suspect pool to a very finite set.

And the Birthday Paradox doesn't enter into it at all. To solve a crime, they are looking only for one very specific individual: the guy who left his DNA all over the crime scene. They don't care if Alice and Bob share common markers, they only care if Alice matches the suspect or Bob matches the suspect.

Re:Interesting

[AK Marc]

Not being in the US, the government sometimes follows their own rules or does what they promise.

Re:Interesting

[TheCarp]

> It is interesting to see the different attitudes toward volunteering information to the government. If
> NYC asked something like this, it would be an outrage and participation would be roughly 1% if it
> moved forward at all.

actually, I bet that you would get very high participation rates of people that you ask. The really privacy concerned are a small but vocal percentage.

Frankly, I wouldn't even mind myself in a case like this where there was some assurance that all samples would be destroyed, except for the fact that its very hard to trust such statements when we have already seen evidence of vaccinations being done by intelligence service controlled operatives in Pakistan, for the very purpose of collecitng DNA samples without even patients consent.

A program to actually collect DNA here is going to have enough oversight to prevent the casual or intentional violation of this agreement? Not very likely.

Re:Interesting

[infinitelink]

I don't think you understand DNA testing very well. The tests don't do a one-to-one codon match, which Joe public seems to think (even if he doesn't know what a "codon" is): "DNA is unique and a DNA test identifies it perfectly!": that's not the case, of almost any currently used test. Specific markers are used and the statistical certainties leveraged...but there is a lot of room for false positives, matches in the wrong people, etc.: it's like the time a couple of engineers using the same calculators made a bet on an equation, then input the equations into the calculators and...got two slightly different answers: I remember a guy talking about this experience and how they were all in shock because the probabilities were absurdly (in the mathematical sense) low that this would happen--something that scientists would think impossible--yet it did.

DNA is more of a cluster than that; there's a lot of "random" assignment (i.e. we don't know the inputs, and can't account for them, in a given individual), people are related so you can get cross-matches: identical twins can actually test the same of course, but though very small, there is a chance that so can brothers, cousins, etc. I would not "volunteer" my DNA any day, because the people in government think "DNA, IT MUST PROVE SOMETHING" (and so does the populace), not unlike when they hear "polygraph" they think "NOW WE'LL KNOW IF HE'S TELLING THE TRUTH" (polygraphs are **** btw).

And even if it was one-to-one btw, there are of course SNiPs, TWO sets of DNA (as in, chromosomes come from pairs), epigenetics (both the expression, and with the likes of directed evolution genes there are further changes to the genome...): conceivably just through epigenetics multiple people subjected to similar conditions could have similar changes to their genomes. The real problem, though, is the overdramatization and inflated claims for "science" by the purveyors, speakers, and researchers that depend on fear and paranoia for grants, support, and prestige: the first lesson I had in university biology, in fact, after the professor checked to insure all there were majors, was "remember people, there're only so many cookies in the jar and a lot of hands: FEAR gets money." We need less confidence and more "we don't know ****" kinds of attitudes.

Re:Interesting

[AK Marc]

A few years back in the USA someone (I think it was a reporter) decided to test the accuracy of the DNA testing companies. They sent in samples as if from a criminal investigation that would NOT match. Almost all the companies returned 'matches'. That really throws into question the results of the companies, even though the science is solid.

If you are thinking of the one I'm thinking of, they essentially were statistically stupid, and though that was worth a story. DNA isn't 100%. Nobody claims it is. And the reporter didn't know what birthday collisions are (or lied through omission in the report). So false positives are expected, and the reporter got them at a rate higher than they ignorantly expected, and thought that was novel. It wasn't. They were idiots. And it reflects more poorly on the state of a liberal arts education than DNA matching.

Re:Interesting

[AK Marc]

Not when you are doing these dragnets where you are testing pools of people against full databases. When doing that, you do get birthday collisions.

Re:Interesting

[AK Marc]

If the juries were of average intelligence, then it wouldn't matter. DNA is evidence. It is not proof.

Re:Interesting

[viperidaenz]

zero involving close family members. Those ones would probably increase dramatically.

Re:Interesting

[nedlohs]

People are dumb.

But yes, I certainly wouldn't be submitting my DNA in that case, and in fact I'd be going on a vacation if my family members were going to submit theirs.

Re:Interesting

[swillden]

Given that DNA has a whole lot more than 366 possibilties, how many people do you need to have two that were born on the same day, for a properly randomized group of people?

Any biometric can be roughly characterized with a "resolution" number, which is basically how many separate "bins" it will divide people into, given a specific set of testing parameters. Birthday has a resolution of 366. So, a particular DNA test which analyzes a certain number of base pairs and has a particular degree of fidelity might, for example, categorize everyone into one of a million categories. One of those categories is already occupied by the killer, so if you test two million people, on average (and assuming the test distributes people relatively uniformly, rather than clustering larger numbers into some of the buckets) you'll expect to find two matches.

Applying the Birthday Paradox, then, if n is the resolution, you need approximately 1.177 * sqrt(n) people in your sample to get a 50% chance that at least two of them are considered the same. Assuming n = 1,000,000, this means you need 1.177*1000 = 1,177 people, roughly.

Note, though, that the "resolution" view of a biometric measurement is a pretty rough approximation because the "edges" of the bins are fuzzy. Any measurement has some number of "false positives" (individuals whose measurements are sufficiently close that for a given match threshold they're considered the same) and some number of "false negatives" (multiple readings from the same individual whose variance is sufficient to fall outside the match threshold). There are various parameters in most systems that can adjust the false positive and false negative rates, but decreasing one increases the other. The "equal error rate" (ERR -- yeah, I know the letters don't match the words) is found by adjusting the parameters until false positive and false negative rates are the same, and this rate provides another measure of system accuracy, but it's not common that ERR is used in real systems.

I think DNA testing is different from most other biometrics in that it has a zero false negative rate -- that is, two non-degraded and uncontaminated samples from the same individual, subjected to the same testing process, will always indicate a match, but I'm not 100% certain about that. And degradation and contamination could still produce false positives. But "resolution" is mostly a measure of false positive rate, so it's still a useful way to talk about DNA testing.

Oh, it's also worth pointing out that the math behind the Birthday Paradox is not in any way specific to measurements of people. I often use the same calculations when deciding how many bits of a hash I need in order to be certain that collisions are sufficiently unlikely.

Re:Interesting

[Frequency Domain]

If you have a pool of N possible outcomes, and outcomes are pretty uniformly distributed across the pool, the probability of a duplicate existing is around 0.99 by the time you sample 3*sqrt(N). For the birthday problem, this means 3*sqrt(365) or about 57 people in the room means 99 times out of 100 there's at least one duplicate birthday. For a hash table with a million storage locations, you can be pretty sure you'll see key duplication by the time you have added a mere 3000 elements to the table. That's why collision resolution schemes are necessary even in relatively sparse hash tables.

If outcomes aren't uniformly distributed, they bunch more in certain locations and the probability of getting duplicates goes up.

Re:Interesting

[Filip22012005]

There is no jury in a Dutch court. The judges decide.

Re:Interesting

[Filip22012005]

I don't think you do. One of the sets is fixed, because it was found on (in) the victim's body. The bday paradox occurs because you match everything to everything else, inflating the probability of a match.

Re:Interesting

[HiThere]

That said, the requirement for an absolute majority is VERY desireable. It's still true that you can't trust anyone with power, but it's much worse if a plurality is sufficient.

FWIW, an absolute majority is one of the benefits of both Instant Runoff Voting and Condorcet. I personally perfer Condorcet voting, but because it's not sufficiently better than Instant Runoff, and Instant Runoff Voting is easier to explain, IRV may be the better system.

You still shouldn't trust the government, but with a requirement for an absolute majoirty, it's reasonable to distrust it less.

Re:Interesting

[plover]

Crime scene samples of DNA are of two types: incidental and direct. Incidental might be the DNA you leave by sneezing, exhaling, or shedding dead skin flakes. Direct would be that collected from body fluids deposited by the attacker. It would be hard to claim contamination of a direct sample - not that many non-rapists are accidentally going to leave that kind of evidence behind. They don't just run one cell's worth of DNA. What they do is to run sequences on several different bits of the sample - if they all match, it's not contaminated.

No, they don't run a full genome sequence, but they don't have to. The more alleles they compare, the higher the certainty. Statistics quickly take over and at some point there is no longer the possibility of a chance match, and it simply does not take all that many markers. The US Combined DNA Index System (CODIS) tracks 13 different markers, and is considered strong evidence. Matching 8,000 would be crazy strong proof that either the suspect or his zygotic twin brother committed the crime.

Re:Interesting

[dingen]

The fact they're even asking for DNA again is evidence in itself they actually do destroy the material.

They already asked about 20.000 people for their DNA in 2000. They wanted to test again now, because recent developments in both technology and legalization have made it possible to search for family relations as well in the found DNA material from the crime scene. They couldn't use any of the material they gathered in the previous investigation for this new test, because it was all destroyed.

Re:Interesting

[swillden]

You should find it scary. The odds of a false positive are probably much higher.

The DNA database in the US has found matches between a black man and a white man if you point it at itself.

Matching a database against itself is a great way to calibrate the accuracy of a test, but not a good way to understand the probability of false positives when comparing a specific sample (from a crime scene, for example) against a population. The mathematical relationship between these two match probabilities is straightforward but not very intuitive.

The most well-known example of this counter-intuitiveness is what's called the "Birthday Paradox", which is that while most people would think that in a room of, say, 25 people, the odds would be fairly low that two of them have the same birthday (month and day), in fact the odds are quite high, nearly 60%. With 30 people it's 70%. With 35 people over 80%. By the time you get 60 people, it's a near-certainty.

Even if your DNA test has only a one-in-a-billion probability of a false positive when matching two specific samples (and I don't think any DNA test commonly used is that precise), if you point it at any database with more than 37,000 people you have a 50% chance of finding a false match between some pair of them. If you have a database of 100,000 people you have a 99% chance of at least one false positive. Expand it to a million entries and you'd need a DNA test with an astronomically low false positive rate in order not to have a false positive.

But none of that has much to do with the chance that your DNA matches that of a specific sample from a crime scene, other than the fact that searching for false positives in pairwise database matches is a good way to compute the average false positive rate.

Re:Interesting

[Pieroxy]

Did you read my third sentence?

Re:Interesting

[HiThere]

I don't know about currently, but past investigations have found a VERY high error rate in the reports from sequencing labs. High enough that I don't know whether it's carlessness, sloppy technique, or just not caring what answer they give.

It's true that in an ideal situation, DNA would be very good evidence, particularly in a case of rape. I'm not sure, however, that I would trust the evidence given what previous studies of lab error rates have shown. (That said, this IS a different lab, and this IS several years later. Maybe things aren't as bad as they used to be. But what I'm talking about was NEVER technical limitations...though those are present, too.)

Re:Interesting

[cheater512]

Yeah except most people forget that DNA is utterly useless to us.

Think about it like a barcode on a box of breakfast cereal. Completely useless to everyone unless you want to accurately determine the product and price.
No one gives a damn about barcodes.

Re:Interesting

[AK Marc]

I'm not saying this particular case is, but I've seen "failues" of the system where they matched 100 in a pool of 1,000,000 and found more collisions that they'd expect. It isn't a true full-mesh scenario like the birthday problem, but it's a pool against another pool with stastical matching not being intuitive.

Re:Interesting

[Anonymous Coward]

It's not that surprising actually: this is not NYC. This was a murder in a rather small community. And while the murder rate in NYC is 6.4 per 100.000 citizens per year, the average for this entire country is about 1 in 100.000 citizens per year. This is probably far less for a rural area like this, and also far less seeing that this is was a 16 year old schoolgirl that was raped and murdered. It's the only murder of its kind in a really really long period. Plus people were pointing at the nearby asylum seekers center ('the foreigners have done it!')- which very very likely has nothing to do with this murder at all. So a lot of people are very happy if this gets solved.

Also strict conditions were in place: the DNA obtained could only be used for this investigation, not for anything else. And it's on a strictly volunteer basis. There was no threatening if people did not volunteer. And around here people aren't as anxious about the police or the government. So with that background, it's far less surprising that almost everyone volunteered and there weren't many privacy concerns.

What I think is worrying is that now opinion-pieces start getting published in newspapers and newssites, saying that everyones DNA should be stored in a central database. Using this case as an example.

sources:
murder rate in NYC http://en.wikipedia.org/wiki/Crime_in_New_York_City
murder rate in the Netherlands (from 2008): http://www.cbs.nl/nl-NL/menu/themas/gezondheid-welzijn/cijfers/incidenteel/maatwerk/2009-2857-mw.htm

Re:Interesting

[interkin3tic]

Because I'd rather keep what we have: a state where there may be higher incidences of rape and murder, than a state where the government has my DNA on file. Murder and rape can always be countered effectively by methods we have now. And if crime gets too bad, it's not too hard to turn that situation around. Erosion of privacy, and police state on the other hand are situations that are pretty much permanent. You can always put more cops on the street and be careful if you're worried about getting shot. Law enforcement with too much power on the other hand pretty much requires moving to a different country, or a revolution.

Re:Interesting

[abirdman]

But only the guilty have something to lose in the case of mandatory DNA tracking. Why protect perpetrators?

Re:Interesting

[HiThere]

They *AREN'T* doing a complete match. Not even when they have their suspect identified. (Well, maybe the Dutch do. The price has dropped enough to make that reasonable.)

So you DO get birthday paradoxes. Now if, once you get your suspect, you do a complete match, then you eliminate the problem. (Unless he has an identical twin, in which case you need to test for epigenetic modifications...only guess what, not all of the cells in your body have the same epigenetic modifications. If they're testing sperm, this comes with additional sets of problems that I'm not up on, as I'm not a biologist.)

For which among which reasons a DNA test should never be construced as proof of guilt, not even in rape. You also need other evidence. (It is, however, a strong indication. And should enable you to focus your investigations in a way that's usually useful.)

Re:Interesting

[HiThere]

Being reminded of exactly what the birthday paradox was, I wish to retract the claim that it applies in this situation.

The probabllity is STILL a lot higher than a naive estimate, but that's not the reason.

P.S.: Another reason that it's high is the lab will be under pressure to find a match. And it's not unknown for labs to fudge their results, or even make mistakes. There are other reasons.

Re:Interesting

[canadiannomad]

I envy you. We used to have a similar system in Canada...

Re:Interesting

[cheater512]

Erm they do essentially take a hash.

Do you really think when you do a police DNA check that they sequence your entire genome?
That costs tens of thousands of dollars. No they do a much simpler test.

It is simply a human barcode.

Re:Interesting

[HiThere]

Your estimate of the probability assumes that all results are correct, and none have been fudged to match a pre-determined answer. That's mathematics, not the court system. In fact, not even the labs. Labs have a much higher error rate than you expect, and it's often biased to maintain their business. Want proof that you are descended from King Richard I, you can probably buy it, no matter what your ancestry.

(P.S.: Rumor has it that he didn't HAVE any descendants. This may, of course, be incorrect.)

Now labs that do official business are, presumably, held to a higher standard. But how certain are you that they always live up to it. Do they know what their target is? The standard approach for certainty is that they should do the sequencing without knowning the desired result. Reports indicate that this is, or was, not common practice. (Back when annealing was the standard method for doing a match, this would have been impossible. But when the methods changed, did the procedures?)

OTOH, "I only know what I read in the papers.". They may be popular science articles, but they aren't extremely reliable, only fairly reliable. And Holland is not the US. And the articles I read were years ago. Perhaps they don't apply anymore, or over there. But don't let math blind you to sources of error and bias that you aren't considering.

Re:Interesting

[JaredOfEuropa]

You're kidding, right? Our (Dutch) minister of justice recently suggested it might be a good idea to use DNA gathered and stored for research (with the donors being told that it would be used for that specific reason alone) for criminal investigations like this one as well.

The problem with Dutch politicians (especially with the current government) is that they often are very practical. Which is great if you want to get something fixed. The problem lies in the fact that they forget or ignore base principles in the process. To them, civil rights are not a boundary not to be crossed, but merely an impediment to getting results, and always up for negotiation.

Re:Interesting

[swillden]

Your estimate of the probability assumes that all results are correct, and none have been fudged to match a pre-determined answer.

Yes, I thought that went without saying. Fraud and human error introduce additional uncertainty.

Re:Interesting

[Macgrrl]

Not trolling, but it seems to me that if everyone's DNA were on record the crime rates would drop through the floor.

You'd think so, wouldn't you. But if you read the summary, the guy in question volunteered his own DNA which came back as a 100% match. Most criminals aren't that smart. They frequently believe they won't get caught - if they even think about it at all.

Having sentencing that is intended to be a deterrent - up to and including the death sentence in some states - doesn't stop people from trying to get away with murder.

People committing assault/rape/murder are rarely thinking with their rational brain when they commit the crime.

Re:Interesting

[Firethorn]

Good info - I know about the math and birthday paradox aren't unique; I was just looking to see if anybody had worked it out for DOB, and not just birthday. I figured it'd show how checking 7-13 points might not seem like much for positively identifying people, but how at 13 points, even if there's only ~100 options per point, it's rather unlikely for there to be a match short of twins even considering the world population of ~7B

100^13=12 Trillion people needed to have a 50% chance of having two match randomly.
100^7, the earlier standard, on the other hand, you'd only need 12M, so in a nation of 300M, I'd consider it insufficient proof. Certainly enough to haul somebody in and dig deeper though.

Re:Interesting

[McGuirk]

Perhaps I'm missing something, but is there a downside to the government having everyone's DNA or fingerprints on file? It's different than being watched all the time. It's not a privacy invasion.

Re:Interesting

[Incadenza]

We don't have jurys here. Judges with a false sense of probability can get corrected by a higher court. http://en.wikipedia.org/wiki/Lucia_de_Berk

Re:Interesting

[s73v3r]

Until someone decided to go through the DNA database looking for other markers of disease in an effort to prevent those markers from spreading.

Re:Interesting

[Firethorn]

For the birthday problem, this means 3*sqrt(365) or about 57 people in the room means 99 times out of 100 there's at least one duplicate birthday.

That was already answered further up. What I was trying to ask was "Date of Birth", by which I meant going from looking for "January 27th" to "January 27th, 1968" as the specification for collision. Also, you have to realize that there's actually 366 possible birthdays on leap years; people with a birthday of Feb 29th are a lot rarer than the others, but still exist.

You go from 366 possibilities to ~26k if you're looking for the year as well. You'd need 484 people to have a 99% chance of somebody being born on the same day and year as somebody else in the crowd.

Re:Interesting

[s73v3r]

That is a completely absurd notion. If you can't trust your government, then you haven't done enough work in ensuring that it is a proper one.

Re:Interesting

[nedlohs]

8000 people to match with, not markers.

And yes as I said if you have a reasonable suspect and you test his DNA and it matches 9 markers it's extremely likely that DNA was from him. However, if you take your DNA sample and match it against a database of 100 million DNA samples and consider that there's potential errors from collection methodology, to lab processing, to data entry/transfer it's not so clear that things random/eroneous matches are "no longer a possibility"

Re:Interesting

[Pseudonym]

Erm they do essentially take a hash.

No. They look for 13 specific short tandem repeat loci which are known to have fairly good discriminating power.

Re:Interesting

[swillden]

at 13 points, even if there's only ~100 options per point

Are there that many options per point?

A brief search didn't turn up any estimates of theoretical false positive rate for CODIS, but Wikipedia did have this to say about SGM+, the system used in the UK:

Since 1998, the DNA profiling system supported by The National DNA Database in the UK is the SGM+ DNA profiling system which includes 10 STR regions and a sex indicating test. STRs do not suffer from such subjectivity and provide similar power of discrimination (1 in 10^13 for unrelated individuals if using a full SGM+ profile). It should be noted that figures of this magnitude are not considered to be statistically supportable by scientists in the UK, for unrelated individuals with full matching DNA profiles a match probability of 1 in a billion is considered statistically supportable.

So even the theoretical maximum resolution for SGM+ isn't 100^13, but only 10^13. which means you only need about 3.7M people to have a 50% probability of a false positive, and the statistically-supportable resolution is four orders of magnitude lower than that -- meaning you only need 3700 people for even odds of a false positive.

CODIS may be a little better than SGM+ (or it may be worse), but I strongly doubt that it's 13 orders of magnitude better. I doubt it's even two orders of magnitude better.

Re:Interesting

[UnknownSoldier]

> I think you're quite a sick human being if you refuse to give a DNA sample purely because it's the government asking you

Ah, to be young and naive of the 5th amendment in the US ...

You're really don't understand "due process" do you?

Re:Interesting

[tbird81]

Yeah, sounds plausible.

Re:Interesting

[tbird81]

Actually it's a rapist and murderer hunt.

Most people in the world aren't backward, DNA is evil, conspiracy theorists, like Slashdot is full of.

Only a nerd would want a rapist to go free because "it's DNA" and "that's bad because of the insurance things".

This place makes me sick some times.

Re:Interesting

[cheater512]

Does that not function more or less like a hash? I was using it as an analogy.
You can't tell your hair colour or any other specific details from it, just like a hash.

Re:Interesting

[pipedwho]

But none of that has much to do with the chance that your DNA matches that of a specific sample from a crime scene, other than the fact that searching for false positives in pairwise database matches is a good way to compute the average false positive rate.

If if the odds of 'me' being a false positive match is extremely low, I still feel sorry for the one poor bastard in that database that did match and had no alibi because he was home alone watching a Star Wars marathon.

Re:Interesting

[wallbase]

At least he post under a username to allow some credibility and history to his posts, AC.

-- wallbase (a fresh account for an old Slashdotter).

Re:Interesting

[Pseudonym]

Not really, no. It's more like a cross-section.

Re:Interesting

[swillden]

But none of that has much to do with the chance that your DNA matches that of a specific sample from a crime scene, other than the fact that searching for false positives in pairwise database matches is a good way to compute the average false positive rate.

If if the odds of 'me' being a false positive match is extremely low, I still feel sorry for the one poor bastard in that database that did match and had no alibi because he was home alone watching a Star Wars marathon.

Right, but keep in mind that even that is different from pairwise database matches. To illustrate: If there's a 1 in 1 million chance of a false positive, then there's a 1 in 1 million chance of matching me. To get a 50% chance of finding some poor random sap, they'd have to check the crime scene DNA against 693,000 people. To have a 50% chance of finding a pairwise match in a database (checking every entry against every other entry), you'd only need a database of 1177 people.

The three problems -- matching a sample against a given individual, matching a sample against a database and matching a database against itself are very different scenarios.

Re:Interesting

[TheRealGrogan]

I certainly will not be brow beaten into sacrificing MY freedom and privacy for fishing expeditions to catch criminals. Being falsely accused or even just investigated by a bunch of overbearing cops is more harassment than I will tolerate. Call me all the names you want, at least "tool" won't be among them.

Even in the intended case of a relative being an alleged match... what then? Are they to be interrogated and harassed into providing their family tree? Only a complete and utter moron would submit to that in the first place. Yes, I know, the world is full of those people who think they are innocent and have nothing to fear from The Law. Wait until you're on the receiving end of a bunch of sociopathic assholes who think the end justifies the means.

Re:Interesting

[Anonymous Coward]

Do you realize that if we only had laws forbidding women from traveling alone in public without being escorted by a male relative how many rapes we might prevent each year?

That's an absurd comparison. Donating DNA doesn't constrain liberty in any meaningful way.

I generally agree with Thread Parent. What's the disaster scenario here? I'm no fan of Big Government, but for something like this I think the resistance is just irrational FUD.

Re:Interesting

[MightyYar]

I like approval voting, exactly because it is easier to explain than most Condorcet methods. While far from perfect, I still think it is better than plurality or IRV.

Re:Interesting

[chrismcb]

If all the women wore burqas, rape might also drop through the floor.
If all men were castrated rape might drop through the floor.
I'm sure we can come up with many thinks that will make rape drop through the floor. But that isn't a reason to introduce them,

Re:Interesting

[cheekyjohnson]

The fact that they're treating everyone as a criminal is what I don't want to happen. We already see this with the TSA, and I don't want more of it.

Re:Interesting

[cheekyjohnson]

Nothing to hide, nothing to fear.

Re:Interesting

[tragedy]

It gets pretty scary when you start to consider just how many little bits of you fall off and float away through the air every day. All those hairs and skin cells, etc. end up somewhere. They can end up stuck to someone and end up on the other side of the world. With sensitive enough tests, all those little bits can be found and traced back to you, and all of a sudden, you're being brought in to explain what you were doing at a crime scene you never visited.

Then there's the simple fact that biometric identifiers aren't really as unique as people make out. Having everyone's fingerprints on file seems like it would be a great idea, until you realize just how many people actually have fingerprints which are essentially indistinguishable. When you have a suspect based on other evidence and you can compare their fingerprints to ones found at the scene, it's a great piece of additional evidence. When the only evidence you have is a fingerprint found at the scene and it implicates thousands of possible suspects, that's more problematic. Bringing them all in for questioning goes way beyond reasonable. The same is true of DNA. The markers they check for can find just one, or a small number, of matches from a large sample group. Increase the sample group size to the entire population and, all of sudden, a lot of people come up and have the pall of suspicion cast over them. More extensive testing can narrow it down, but the police may simply opt to bring all the positives in and interrogate them. They also might just decide to charge whichever match lives closest, or who matches some vague eyewitness description of someone who was walking down the street at some point within a few hours of when the crime is estimated to have happened. Then that person can spend a few years, and enough money to destroy the rest of their life, to get to the point where they can demonstrate clearly in court that a more complete DNA comparison clears them.

Re:Interesting

[drkstr1]

Well I for one, wouldn't want to bet my life on the "average intelligence" of the populace. In my experience, that average is pretty low.

Re:Interesting

[SecurityGuy]

Yes. I also read your fourth.

Re:Interesting

[hairyfish]

This attitude depends on where you live. I think in bigger places there is more room for abuse because sheer population size means people don't have to care about other people they don't know. But in smaller towns where everyone knows everyone there isn't the same level of a paranoia or corruption.

Re:Interesting

[hairyfish]

Yeah fuck the draconian government and there stupid rules. Why should we even have to go to court when requested? Fuck them, I prefer a free society with no rules, like say Mogadishu or Lagos...

Re:Interesting

[Mirvnillith]

So law enforcement with more and more cops on the street to counter crime will never be too much power?

Re:Interesting

[tehcyder]

I'd rather err on the side of having murders and rapes go unsolved, rather than err on the side of police having everyone's DNA sequences.

If you commit rape and murder and are convicted by your DNA after a fair trial, I don't see the problem. You're guilty of the crime and should be punished.

Now, the question of whether DNA evidence is quite the 100% guaranteed foolproof method some people claim is a different issue, but it should still be covered by the "fair trial" proviso.

Arguments about the police planting DNA evidence and fitting up suspects for political reasons are pure paranoid fantasy: if they wanted to they could do that already without using DNA quite easily.

Re:Interesting

[tehcyder]

There is no end to the amount of crimes that could be prevented or solved if only we were ready to embrace draconian governmental invasions of our privacy and restrictions on our freedom of choice. Do you realize that if we only had laws forbidding women from traveling alone in public without being escorted by a male relative how many rapes we might prevent each year?

Being persuaded by the likelihood of getting caught from murdering someone is only an invasion of your privacy and a restriction on your freedom of choice in the most outlandish libertarian fantasies, where any "government interference" is inherently evil.

You will still have the "freedom" to rape or murder someone, as this isn't Minority Report style pre-cog yet, it just means you're highly likely to get caught and convicted for it. Excuse me for not blubbing over the rights of murderers and rapists to get away scot free with their crimes.

Re:Interesting

[tehcyder]

People committing assault/rape/murder are rarely thinking with their rational brain when they commit the crime.

So what? It still hopefully means that they can be caught and convicted more easily, I just don't see why that can ever be a bad thing.

Re:Interesting

[tehcyder]

Trouble is..how can you know you can trust others in the govt years down the line?

Democracy. In the end, it's the only thing you can rely on.

Re:Interesting

[tehcyder]

actually, no - it's interesting to see what actual happens, because the question is - how/why does this DNA match actually matter?

It's nearly as impossible to associate DNA at a crime scene with an individual being actually involved without further proof - otherwise this is in the same category as trying to assign an IP address to an individual.

I'm fairly sure DNA is a bit more useful than this, or they wouldn't have bothered with the appeal for volunteers in the first place.

And yes, obviously, you have to end up with enough evidence to convict someone at a trial, no one is suggesting you have some sort of trial by CSI: "it's a match!" "Right, bang him up in prison for fifty years wiout trial then".

Re:Interesting

[tehcyder]

Since it was murder/rape I guess that the rapist left the dna in a place where only a person having had sex with the victim would leave it sort of...

Exactly, if your DNA is found in the victims's vagina, your "she must have brushed against me in the street" defence isn't going to sound too convincing.

Amazingly, lawyers and judges do actually take things like plausibility, possibility and probability into account in criminal cases. It's never as simple as "we have one piece of DNA evidence, therefore you're you're guilty".

Re:Interesting

[tehcyder]

I find this method seriously scary due to the probability of a false positive. I mean, suppose you have a system that only fails once in a million times and the killer has already left the country. You ask the two million people in the metropolitan area to submit DNA. You get on average two matches. One doesn't have an alibi. You take him to trial and tell the jury that he not only doesn't have an alibi, he had a 1 in a million DNA match. It sounds pretty convincing. It is very possible the jury won't have the understanding of statistics to ask "was this a sweep or did you only test a couple of likely suspects?" Nor is it likely that the information will be volunteered by the court.

In any sane legal system you couldn't convict someone on one piece of positive evidence (DNA) and one negative (no alibi).

If you have an insane legal system where this could happen, you're fucked anyway.

Re:Interesting

[sveinungkv]

Or if you knew that when they did wrong it could be amended just by a proper re-vote instead of having to implement drastic measures like carving the right to bear arms into a constitution which will fly out of the window anyway if a government really wants to implement evil...

Democracy is no guarantee that you can trust the government. If a politician knows that the electorate can't stop him he may decide to end democracy if the electorate chose the "wrong" option. If the electorate is well armed he is forced to think twice as he may get hurt while ending democracy. If democracy remains it still won't stop the majority from following the European tradition* of voting to violate the God given rights of other people. If the minority is well armed the majority is forced to think twice as they may get hurt while implementing the new policy.

Information the government has on you won't disappear when the government changes. In the future the government, with or without the consent of the voters, may use DNA to choose their next victims. The DNA of some individual they want to get rid of can be planted as false evidence of a crime. Targeted bio weapons may also appear. When the Nazis invaded Norway during WWII they found government registers that specified if the person on the list was Jewish or not. Guess how this information was used.

* The popularity of Adolf Hitler and Joseph Stalin among their European subjects wasn't unique. Here in Norway the Labor party government did forced sterilizations (link in Norwegian) as a part of its socialized medicine. People kept voting for them. (The law was removed in 1977. The Labor party is a part of the current ruling coalition. An award carrying the name of Karl Evang's name is still handed out. As far as I know the Labor party no longer support forced sterilization)

Re:Interesting

[tehcyder]

it's like the time a couple of engineers using the same calculators made a bet on an equation, then input the equations into the calculators and...got two slightly different answers: I remember a guy talking about this experience and how they were all in shock because the probabilities were absurdly (in the mathematical sense) low that this would happen--something that scientists would think impossible--yet it did.

Interesting, do you have any more details on this? What equations? What were the probabilities? What actually happened?

Re:Interesting

[tehcyder]

Thank God someone finally posted this. For a geek site there are some very strange ideas about statistics floating around here.

Re:Interesting

[tehcyder]

The DNA database in the US has found matches between a black man and a white man if you point it at itself. They only look at about 12 spots and sometimes use just 9 to identify someone.

Surely if that was presented in court, the defence would be able to drill a hole right through it?

Re:Interesting

[plover]

Sorry, 8000 samples, yes.

But this argument all seems tied up around a very extremist idea that one and only one match of a few digits in a database means the courts will find him guilty and hang him. One match will only lead the police to the door of a suspect, where they will not only look for other evidence, but also perform another series of DNA tests. Any errors in collection would then be exposed, and if the suspect is the wrong person, he will be exonerated as a result.

In the U.S. in the case of "forensic evidence-to-registered offenders" matches, the CODIS database only provides a list of candidate matches, and is not acceptable by itself as evidence. Once the candidate is identified, a qualified expert has to analyze the quality of the match. CODIS offender samples are collected one of two ways: via blood draw from convicted felons and prisoners; or by a cheek swab from a person indicted for certain kinds of felonies (kidnapping, sex crimes, violent crimes, burglary). Both require trained personnel to collect; the data in the database is considered reliable.

In some cases, DNA can only establish the likely presence of an offender or his property at or near the crime scene. Blood is possible to explain, as it's not uncommon to accidentally spill, and may be present on surfaces like knives. But in the case of rape or other sex crimes it's especially hard to mistake the sample DNA's source from other contaminated sources. Even so, they can and will perform the tests multiple times on multiple samples taken from the victim, (and from a new sample collected from a cooperative suspect), to ensure that they didn't pick up something contaminated.

But it's not a one-match-and-you're-guilty system.

Re:Interesting

[tehcyder]

That's because NYC would keep your DNA on file forever, and use it to bust you for things that aren't even crimes, like protesting.

If "the government" wanted to arrest you for protesting or other political offences, all they'd need to do is wait for the inevitable stone throwing (or else just get a couple of undercover officers to start it) then send in the riot police to grab you and do you for a whole raft of different crimes that don't involve DNA evidence.

If somewhere like the US is a police state, it's a pretty pathetic one. Thankfully.

Re:Interesting

[MeanderingCode]

Do you realize that if we only had laws forbidding women from traveling alone in public without being escorted by a male relative how many rapes we might prevent each year?

I don't have a reference on hand, and the sad state of my mobile device makes it too time consuming to dig one up, but most studies agree that the vast majority of sexual assault crimes are committed by someone the victim knows, with a non-trivial percent of assailants being male family members.

I realize you were forming an example for a more generalized argument, but in the case of Constitutionally questionable social structures, being accurate is of paramount importance.

Re:Interesting

[cayenne8]

Democracy. In the end, it's the only thing you can rely on.

True..but times change...

Not to mention, that even if you're careful, you can still get the wrong kind of people elected...and you're usually pretty much stuck with them till next election, during which time, damage can be done to your life.

Re:Interesting

[Frequency Domain]

For the birthday problem, this means 3*sqrt(365) or about 57 people in the room means 99 times out of 100 there's at least one duplicate birthday.

That was already answered further up.

So another poster clicked their submit button a minute or two before I did. Your comment seems rather gratuitous given that we were both trying to clarify things for you.

Also, you have to realize that there's actually 366 possible birthdays on leap years; people with a birthday of Feb 29th are a lot rarer than the others, but still exist.

Actually, the mathematically correct answer is a convex combination of the results for N=365 and N=366 with weightings 3/4 and 1/4, respectively. If you're going to pick a single number as representative of the answer, guess which one is closer? Besides which, all of this is premised on an assumption that birthdays are uniformly distributed throughout the year. That's close enough to get insight, but not actually true - there is a slight seasonality component in human birthrates.

You go from 366 possibilities to ~26k if you're looking for the year as well. You'd need 484 people to have a 99% chance of somebody being born on the same day and year as somebody else in the crowd.

You definitely lose the uniformity assumption by adding year - a larger proportion of the population are in their first couple of decades than in their 70's and 80's. As I mentioned earlier, non-uniformity actually increases the likelihood of duplicates so 484 should be an upper bound on the 99th percentile.

Re:Interesting

[nedlohs]

Apparently it is a "one-match-and-you're-guilty" system. Here's two cases in which the only possible evidence was the DNA match (since the two people were in fact innocent) and it was enough to get a conviction: http://www.lvrj.com/news/dna-related-error-led-to-wrongful-conviction-in-2001-case-125160484.html or http://www.smh.com.au/national/dna-lab-error-led-to-false-conviction-20091002-ggj6.html. Of course sometimes you get lucky and only get to spend a few months of your life in custody before they notice they screwed up: http://www.bbc.co.uk/news/uk-england-17324912, http://www.bbc.co.uk/news/science-environment-19412819.

And yes your "qualified expert"s are great. You know aside from minor issues like putting the wrong name on samples and contaminating samples.

Re:Interesting

[Troed]

You're kidding, right? Our (Dutch) minister of justice recently suggested it might be a good idea to use DNA gathered and stored for research (with the donors being told that it would be used for that specific reason alone) for criminal investigations like this one as well.

FYI, that did happen in Sweden. The donors are all citizens born after 1975.

http://falkvinge.net/2012/07/19/sweden-paradise-lost-part-3-comprehensive-population-dna-database/

Re:Interesting

[cavebison]

I'd rather err on the side of having murders and rapes go unsolved

You, sir, have assumedly never been murdered or raped. Here, have a gold star for mediocrity.

Re:Interesting

[cavebison]

There is no end to the amount of crimes that could be prevented or solved if only we were ready to embrace draconian governmental invasions of our privacy and restrictions on our freedom of choice.

How silly you people are. Do you complain that your bank knows everything you purchase, when and where, on your credit card? Are you prepared to march the streets to end Facebook's privacy invasions? Do you complain about your curtailed freedom to drive through red lights or go twice the speed limit? Do you complain about speed cameras "spying on everyone" just in case someone breaks the law? Do you complain to shopowners that their CCTV camera is violating your precious privacy?

We live lives surrounded by rules, regulations, restrictions and invasions of privacy. We accept them all for one reason - because we understand the need for them, in order to live in a reasonably functional society. You are NOT against rules per se. You are NOT against invasion of privacy per se.

Don't fool yourself like everyone else does. You accept those things with open arms. What you aren't convinced of is simply whether this SPECIFIC rule (keeping all DNA on file) will be a benefit that outweighs the privacy invasion. Nothing more, nothing less. Just say simply that, and you won't sound like a mindless reactionary.

Re:Interesting

[BadgerRush]

The big difference is that in Netherlands they can trust law enforcement to destroy the samples after that investigation was done. In the other hand, in NYC you can be fairly certain that law enforcement would hold on to those samples and resulting DB, breaking promises and maybe the law with impunity.

Re:Interesting

[poetmatt]

Guess what? that's what governments tend to do in these types of cases, actually.

They're saying it's some kind of DNA match with a *lighter*, but I don't know how that correlates to "he must have murdered her". That is indeed a giant leap of logic if there aren't additional details.

Also, it's a playboy lighter, not a vagina. If you think you can get DNA from a vagina later than a few days you're mistaken. That's why those rape kit things exist - they're not for "later on down the road". 6 months, years? Hint: no.

Re:Interesting

[mariox19]

Your arguments are silly. No one is forced to use credit cards; besides, what are banks going to do with records of your purchases, develop a consumer profile and try to sell you things? No one is forced to join Facebook, and even if they do, you're not forced to share anything you don't want to. Red lights and speed limits are a nonsense argument. As to speed cameras, I and plenty of other people do complain about them, for various reasons. As to shop owners and their CCTV cameras, these are decentralized.

The argument you make is either completely ignorant or you have some kind of hard-on for government. We don't know what the full extent of knowledge about one's DNA will mean, and it's wise to keep it private. Moreover, innocent people shouldn't be bothered as a matter of policy, no matter how "helpful" that is to police work. We don't live for the police or government; they live for us.

It's you who is "mindless," with all your talk of "we" when talking about government. Government is like a gun. It's a great thing to have when it comes to protection, but you don't leave it lying around and you don't let it fall into the wrong hands. Allowing government every type of intrusive "convenience" is the fastest way to put together turnkey totalitarianism. It's bad civic hygiene.

Take your servile mentality somewhere else.

Re:Interesting

[Tuoqui]

Birthday Paradox relies on the same thing...

You're comparing YOUR birthday to the birthday of a number of other individuals. Thus the one sample (DNA on/in victim's body to a large number of potential samples.

That said it may be a lower chance so a larger number is more likely to result in a collission but still the possibility exists. DNA really is only reliable when you're working with one suspect and everythign else lines up.

Re:Interesting

[Filip22012005]

In the birthday problem, you are not matching your birthday to the birthdays of the people present. It's the probability that in a set of n randomly chosen people, some pair of them will have the same birthday. See wikipedia.

Perhaps I'm not getting what you're saying. Because you say "YOUR", and I'm not sure if you actually mean me.

Sounds improbable

[dinfinity]

"As it turned out, the man now in custody turned in his own DNA, resulting in a 100% match."

If he was really the guy who did it: Was he wondering whether the DNA-research would work? Why not just turn himself in?

Re:Sounds improbable

[Romwell]

Well, turning yourself in is admitting guilt and is psychologically hard. This way, he is not directly admitting guilt (he does the same thing 90% of people in the neighborhood are doing), and there's a chance they won't get him, so it probably is much easier to (effectively) turn oneself in this this way.

Re:Sounds improbable

[Hardhead_7]

I wondered about that too. Of course, if a few family members had already donated, and you knew it was only a matter of time before they caught you, it might be worth turning in your own DNA so you can later sow doubt with a "If I were really guilty, why would I have turned in my DNA?" defense.

Or maybe not. Who knows at this point?

Re:Sounds improbable

[RabbitWho]

If 96% of people had done it the social pressure might have been insurmountable. He might have figured if he was the only person in the village who didn't give DNA the police would investigate him and find him anyway, so he might as well give the DNA, hope that there would be a mistake, or hope that he could claim "If it was me, then why did I give them my DNA?"

Re:Sounds improbable

[IamTheRealMike]

The guy had a wife and child. If your wife starts saying "Hey you should do this" it's probably hard to say no to her, even if you know it'll result in doom. After all, if you aren't the type who normally cares about or talks about civil liberties it's probably hard to come up with a negative response that doesn't sound fishy as hell.

Re:Sounds improbable

[nschubach]

The guy had a wife and child. If your wife starts saying "Hey you should do this" it's probably hard to say no to her, even if you know it'll result in doom

If he had a wife like that, he probably did it because it would result in him being arrested.

Re:Sounds improbable

[BLKMGK]

The DNA matched DNA found on a cigarette lighter found in her schoolbag - not DNA from the rape itself apparently. It's possible in my mind that the guy is innocent of rape\murder and guilty of selling a schoolgirl a lighter or her guilty of stealing it. More details need to come out, this isn't "solved" in my mind unless they have DNA evidence from the rape itself that matches.

Re:Sounds improbable

[Baloroth]

If 96% of people had done it the social pressure might have been insurmountable. He might have figured if he was the only person in the village who didn't give DNA the police would investigate him and find him anyway, so he might as well give the DNA, hope that there would be a mistake, or hope that he could claim "If it was me, then why did I give them my DNA?"

That's why the US has the fifth amendment (and why a right against self-incrimination is a good idea in general). Not turning in DNA is not probable cause for an investigation, and if that is why they started investigating him, the case would have a high chance of being thrown out (of course, the family DNA might be enough to establish an investigation). I'm not sure what the law is on this in the Netherlands.

Re:Sounds improbable

[Anonymous Coward]

The DNA matched DNA found on a cigarette lighter found in her schoolbag - not DNA from the rape itself apparently.

The DNA on the lighter matched DNA from the rape itself. The importance of the lighter is that it was sold during the time of the rape in that narrow area - placing the rapist as a resident of that area at the time, and giving high probability that a scan of all the residents would strongly indicate who the attacker was. If the lighter wasn't found, this search couldn't be justified as the rapist could come from anywhere.

Re:Sounds improbable

[bp m_i_k_e]

It was more than a lighter exchange. Matching DNA was found on both the lighter and on the girl's body. That led to the DNA-dragnet. Apparently, the suspect's DNA matched the samples from her body and the lighter.

Re:Sounds improbable

[gr8_phk]

The DNA matched DNA found on a cigarette lighter found in her schoolbag - not DNA from the rape itself apparently .... More details need to come out, this isn't "solved" in my mind unless they have DNA evidence from the rape itself that matches.

Especially when they're admittedly going on a fishing expedition through the entire town. There is no doubt that there would be other peoples DNA on her personal belongings. Probably several peoples DNA from various places. This is exactly the kind of thing people are afraid of when they don't want their DNA in a database.

Re:Sounds improbable

[Frans Faase]

It is important that they were living in a small community. It already has been reported that some family members of the victim had contact with the man who had been arrested. It is thus possible that the victim knew the man. And even if they did not know each other, it is still possible that the cigarette lighter was passed on through a family member. Cigarette lighters belong to those items that are often 'shared' among people, especially among people that have some social relationship.

Re:Sounds improbable

[MozeeToby]

Even if it were DNA from the rape, I would have my doubts about their claimed "100%" number. Let's say it's really "only" 99.99%; they have 8000 samples, what are the odds that someone will match? Then you through in the fact that the 99.99% probably includes a truly random sample, which a small town is most assuredly not, and the odds of finding a false positive increase even more.

Re:Sounds improbable

[Anonymous Coward]

According to TFA, the lighter had DNA that matched trace collected from the girl's body. The lighter is significant because it was being sold in the area at the time of the crime, meaning that the murderer was likely local and not from abroad. This was what motivated the mass DNA testing - it was no longer a shot in the dark.

Re:Sounds improbable

[91degrees]

It's still possible that he is. I'm sure I could conceive of a way his DNA could end up on her body. While I doubt this is the case, it's only fair to let him tell his side of the story.

Re:Sounds improbable

[Crayon Kid]

That's why the US has the fifth amendment (and why a right against self-incrimination is a good idea in general).

Please elaborate on how this is a good thing, because I'm really confused about it. To me it sounds like, the police finally found a way to identify a murderer, but then this 5th amendment thingy comes in and it gets thrown out on a technicality. What's good about that?

I've read the Wikipedia entry about the self-incrimination aspect of it, to prevent confessions obtained under torture for example. But that's a far cry from what we have in this case.

Re:Sounds improbable

[Dorsch]

This has happened before:
Original in German | Google Translate (English)

18,000 men were asked to give samples, ~80% did - among them the perpetrator. Apparently some relatives went and he couldn't come up with a good excuse to skip.

Re:Sounds improbable

[wonkey_monkey]

Not turning in DNA is not probable cause for an investigation

Is "being the only remaining suspect living in the area" cause enough? Also, there's plenty of investigating that can be done without probable cause or a search warrant.

Re:Sounds improbable

[Sulphur]

Well, turning yourself in is admitting guilt and is psychologically hard.

This way, he is not directly admitting guilt (he does the same thing 90% of people in the neighborhood are doing), and there's a chance they won't get him, so it probably is much easier to (effectively) turn oneself in this this way.

And maybe the lab will get it wrong, and mixup the samples; 100% match and 100% wrong.

Re:Sounds improbable

[tibit]

Those "DNA matches" are not. AFAIK, what's matched a very tiny amount of information from the DNA. I figure there may be a reasonable probability that when you've got so many volunteers, there will be a "100%" match. I don't know what kind of "matching" they are using, of course, so feel free to correct me if I'm totally off-base.

Re:Sounds improbable

[Anubis IV]

No, that's patently incorrect. The article (which I read, shame on me) makes it clear that the DNA on the cigarette lighter matches DNA present on the body of the victim:

The decision to launch the dna appeal came after De Vries in May broadcast information about a Playboy cigarette lighter found in Vaatstra's bag which contains dna traces that match the traces found on the schoolgirl's body.

More or less, they found DNA on her body, but had no immediate reason to suspect it was from someone nearby. When they found the same DNA on the cigarette lighter and were able to determine that the cigarette lighter was on sale in that area around the date that the rape/murder occurred, they thought they had reason to suspect a local individual was involved. That's what led to the DNA dragnet.

I do agree that police need to be careful with DNA evidence and not use it as proof of guilt where it implies no such thing, but that does not seem to be the case here.

Re:Sounds improbable

[jitterman]

Good point. I also wonder what Dutch law is as to the admission of DNA evidence in trial is. Is it enough to provide grounds for arrest, but not usable in court? Is it admissible in court but only to be considered as circumstantial. Clearly, IANAL, so I'm curious. Perhaps (as others have said) this allows him to clear his conscience and still have a chance of not being convicted.

Re:Sounds improbable

[rtfa-troll]

What if it's a false positive?

Given that the chance of a false positive is normally between 1 in 100 and 1 in 1000 in DNA tests (this is based on cases where people have actually tested labs by sending them known matching and non matching samples - not the statistics of DNA) and they have carried out 8000 tests, that's pretty likely. Most likely they had multiple false positives, but he's the one which repeated when they retested. If he was actually guilty he probably wouldn't hand his sample in.

The most likely explanation, given that he's a farmer, is that his DNA was present on some food the lab technician put next to the original sample. Now there's no way he can prove his innocence (were were you on the 1st of May 1999? can you prove that?). He's fucked. Serves him right for trusting the police.

Let's see if the Dutch police actually investigate or if they just assume his guilt. From what I've seen whilst probably honest they're pretty narrow minded.

Re:Sounds improbable

[Anonymous Coward]

If you're innocent and the police violate your rights and find no evidence, what is the disicentive for the police. Cause they can't throw away inexistent proofs they didn't find to compensate your rights having been violated.

Re:Sounds improbable

[JudgeFurious]

Aren't they actually investigating the entire village and so if 96% of the men living there have eliminated themselves as suspects it would seem that then focusing on the remaining men who could still possibly have done it would be entirely correct. They'd be looking closer at him because he as one of only a handful of people left who could possibly be guilty.

Re:Sounds improbable

[martijn hoekstra]

"As it turned out, the man now in custody turned in his own DNA, resulting in a 100% match."

If he was really the guy who did it: Was he wondering whether the DNA-research would work? Why not just turn himself in?

It was a cold case. Maybe he forgot he was involved in a murder in the first place. "Oh, that murder case! I forgot all about that one... ...wait, give my DNA back, I don't want to volunteer!"

Re:Sounds improbable

[C0L0PH0N]

As pointed out in other posts, your statement, "not DNA from the rape itself", is completely incorrect. As the article says, "The decision to launch the DNA appeal came after De Vries in May broadcast information about a Playboy cigarette lighter found in Vaatstra's bag which contains DNA traces that match the traces found on the schoolgirl's body. " The DNA WAS found on the girl's raped body. Because it was ALSO found on a cigarette lighter sold locally, that is why they suspected a local person. So his DNA matches exactly that on the raped girl's body! At least, their approach was logical. Just to be clear.

Re:Sounds improbable

[Anonymous Coward]

I HAVE A TWIN defense possibly?

Re:Sounds improbable

[Effexor]

The DNA on the lighter matched DNA from the rape itself. The importance of the lighter is that it was sold during the time of the rape in that narrow area - placing the rapist as a resident of that area at the time, and giving high probability that a scan of all the residents would strongly indicate who the attacker was. If the lighter wasn't found, this search couldn't be justified as the rapist could come from anywhere.

So the killer put his lighter in her bag? Isn't it more likely that it was her lighter and she let someone else use it? In which case the 'narrow area' isn't significant, it just tells you where she got it, which apparently included the town where she lived. Not exactly a shocking clue.

Re:Sounds improbable

[Baloroth]

That's why the US has the fifth amendment (and why a right against self-incrimination is a good idea in general).

Please elaborate on how this is a good thing, because I'm really confused about it. To me it sounds like, the police finally found a way to identify a murderer, but then this 5th amendment thingy comes in and it gets thrown out on a technicality. What's good about that?

Because otherwise the police would be doing dragnets like this constantly. Say there was a murder with a handgun: the police could ask everyone to bring in all their guns they owned for examination, and assume anyone who didn't do so was guilty. Or hell, just send out poll question "did you do x?" and anyone who didn't respond is automatically a suspect. The point is that wanting privacy does not automatically make you guilty (otherwise, the police really could just say "well if you have nothing to hide, why don't you just let us in and plant video cameras or examine everything you own?" or whatever they want. The point is to curb the power of the police, because otherwise it becomes essentially arbitrary).

Re:Sounds improbable

[jythie]

Even with the 5th amendment the US has had problems with dragnets in the past, the police needing a lead and rounding up 'the usual suspects' which in many cases became little more then harassment of weak populations. There is also the historical problem of defending yourself once the police have their eye on you.... there have been countless issues with bad (or just incomplete) science resulting in 'this person did it!' and the person having to prove otherwise on their own dollar.. which when you have these kind of broad searches you will generally find at least _someone_ who seems to be guilty... and then there is incredible political pressure on the police to have not 'screwed up' so they get invested in making sure the person they fingered.

Looking at some comments below, it appears that the DNA did not come from the crime itself but from a lighter found in the victim's schoolbag.. so now we have a dragnet to find someone who once touched a lighter found with a victim, and now the person's life is going to be turned upside down because of it. They may indeed be guilty, but such a broad search method is bound to find SOMEONE who can be presented to the public as the attacker. In the US at least this would probably destroy the person both financially and socially even if they are vindicated. The police on the other hand have lots to gain for finding someone to point to... thus they have a powerful incentive to use such tools but no real consequence for getting the wrong person. In the US at least there is some check to stop such dragnets.

Re:Sounds improbable

[Jedi Alec]

In his particular case both his father and his son had already decided to donate, so even if he hadn't, They'd very likely still have found him based on familial matches.

Add a dose of social pressure and there you go.

Re:Sounds improbable

[CrimsonAvenger]

Let's say it's really "only" 99.99%; they have 8000 samples, what are the odds that someone will match?

A quick check with my calculator shows about 55% chance of a match with 8000 samples and .9999 accuracy on the match.

With a random sample....

Re:Sounds improbable

[Baloroth]

Is "being the only remaining suspect living in the area" cause enough? Also, there's plenty of investigating that can be done without probable cause or a search warrant.

No? Who says the suspect still lives there. And sure, they could do some investigation, but given the age of the case, it's unlikely that would turn up very much in the way of solid proof. If they couldn't find him a decade ago, it's doubtful they could prove he did it now, even if they know who it was.

Re:Sounds improbable

[Culture20]

Because tourists can't buy lighters? There's something fishy about this fishing.

Re:Sounds improbable

[MtHuurne]

The "100%" comes from a tweet by Peter R de Vries, a crime reporter. The spokeswoman for the institute that did the actual DNA matching (NFI) said there is no such thing as 100% certainty. (both links are in Dutch)

Re:Sounds improbable

[wvmarle]

The "didn't turn in DNA" part is not necessary part of the evidence.

It narrows down the list of suspects, if only one doesn't give DNA the investigation can focus on that individual. If that person is indeed the culprit, there is a very good chance that other evidence is found, directly incriminating the person, and with enough evidence search warrants may be received for more detailed searches. If he is not the culprit, there will be no such evidence.

Re:Sounds improbable

[ottothecow]

Except for the fact that any number of people could have been in the area in 1999 without being permanent residents who still live there today.

Re:Sounds improbable

[u38cg]

Not quite. If you take one individual, and try to match him to thousands of others, the chance of a match is low. If you take thousands of people, the chance that some two of them match is quite high.

Re:Sounds improbable

[jittles]

If you can demonstrate that the police willfully and wantonly violated your constitutional rights, you may be able to sue for financial compensation. You typically sue the government that hired the police officers, the department that was supposed to be monitoring the officers, and the officers themselves. Typically you sue for harassment, defamation of character, and the violation of the rights themselves. There are few times when you are even legally able to sue the government, but in this case its a good thing. Of course there have been people that sue the police for things that you and I may consider asinine, but no system is perfect.

Re:Sounds improbable

[Bill, Shooter of Bul]

What? Investigation of an individual doesn't need to meet any kind of criteria. Now a search of them, their property, or their genetic material without their consent would require a warrent and thus probable cause.

Re:Sounds improbable

[Pieroxy]

A regular DNA test has about 1/10000 success rate, but I would think that one can run a more thorough test (for a cost) that is much more precise than that. DNA doesn't have that collision rate.

Re:Sounds improbable

[Runaway1956]

Same thing has been going through my mind. The guy may never have met the girl - he may have dropped the lighter in the road, and she found the shiny thing lying in the dirt and picked it up. Girls of all ages like shiny pretty things.

So - they've located a guy who touched a lighter that the dead girl had in her possession. Now, it's time to do some real police work, and figure out what that means, IF ANYTHING.

Re:Sounds improbable

[starless]

You're totally off-base. At least in that a few thousand people is not sufficient to give a large likelihood of a match. If it did, it would mean
that DNA databases would be useless for solving crimes.
http://en.wikipedia.org/wiki/DNA_profiling

Re:Sounds improbable

[mark-t]

The *ONLY* way you can get a 100% match with a false positive with a legitimate DNA test is if the subject has an identical sibling.

Re:Sounds improbable

[dgatwood]

Actually, that's not the most likely explanation. The most likely explanation is that the DNA sample that they believed came from the assailant just happened to be at the crime scene for any of a million other reasons.

The second most likely explanation is that there's too much homogeneity in the DNA of the Dutch people—too pure a gene pool. DNA tests are likely to have a much higher false positive rate there than in a less homogeneous population like the U.S., and for a small number of loci, that could result in an unacceptable false match rate.

Contamination of the sample after it was taken is way down around number twenty or so in terms of likelihood.

Re:Sounds improbable

[mark-t]

That defense only has a chance of working *IF* one actually has a documented twin.

Re:Sounds improbable

[westlake]

That's why the US has the fifth amendment (and why a right against self-incrimination is a good idea in general).

In US law, the privilege against self-incrimination is ultimately rooted as a barrier against the use of isolation, intimidation and torture to extract confessions.

There is much you cannot be forced to say.

But very few barriers to the physical evidence you may be compelled to surrender.

I am not convinced that, under US law the barrier to launching an investigation against a particular person is anywhere near as high as that needed to support a search and seizure.

Re:Sounds improbable

[SkunkPussy]

contamination, procedural error etc.

Re:Sounds improbable

[RobinH]

They only test specific markers, or that's my understanding.

Re:Sounds improbable

[westlake]

More details need to come out, this isn't "solved" in my mind unless they have DNA evidence from the rape itself that matches.

I have a very real problem here if you are claiming that DNA evidence "from the rape" is only evidence that would support a conviction for rape.

Re:Sounds improbable

[Bengie]

I'm not the best at math, but I've read about a 1/10^9 accuracy in modern DNA testing. If you test 8000 people, then it's 8000/10^9 or 0.0008% chance of a false positive.

I could be completely wrong. If I am, someone correct me please.

Re:Sounds improbable

[mark-t]

Hyperventilating can foil breathalyzer results. Air that is quickly expelled from your lungs after breathing it in will have less opportunity to absorb alcohol content, and reduce the amount of alcohol detected by a breathalyzer.

It doesn't change the level of alcohol actually in your system, however.

Re:Sounds improbable

[SecurityGuy]

Not turning in DNA is not probable cause for an investigation

Sure it is. Maybe you mean it's not enough for an arrest or search warrant. This guy was already being investigated merely because he lived in the right region.

Re:Sounds improbable

[Cederic]

No, it would mean that DNA is not a positive test for guilt.

It can be a positive test for innocence: If my DNA markers differ from that of sperm found in a rape victim then I didn't rape her.

A positive DNA test seems reasonable grounds for further investigation, but is not in itself sufficient evidence of guilt. Even if they tested the full length of DNA (and they don't even get close) there have been many examples of contamination that invalidates results.

Re:Sounds improbable

[rtfa-troll]

A regular DNA test has about 1/10000 success rate, but I would think that one can run a more thorough test (for a cost) that is much more precise than that. DNA doesn't have that collision rate.

That's the theoretical rate based on calculating the genetics of the population; it assumes that you run the scan perfectly. In fact labs make mistakes and cross contamination happens. This is something where the basic principle of science; actually do the experiment and see; must override the theory.

When people actually the lab error rate for genetic tests they get numbers like 1.7 in 1000 measured false positive rate. If you know a set of results where independent blind testing of the Dutch police DNA system has returned better results, please point to your peer reviewed study which shows so. I believe that most police labs aren't even subject to blind testing, so an even higher error rate should be expected.

Re:Sounds improbable

[SourceFrog]

I think it's almost certainly a false positive (or there's something else fishy about this story ... e.g. perhaps it's a ruse to push broader DNA-collecting laws), for the simple reason that, unless it just slipped his mind that he committed a murder, the real murderer would never have volunteered his DNA.

Re:Sounds improbable

[NotSanguine]

That's why the US has the fifth amendment (and why a right against self-incrimination is a good idea in general).

Please elaborate on how this is a good thing, because I'm really confused about it. To me it sounds like, the police finally found a way to identify a murderer, but then this 5th amendment thingy comes in and it gets thrown out on a technicality. What's good about that?

I've read the Wikipedia entry about the self-incrimination aspect of it, to prevent confessions obtained under torture for example. But that's a far cry from what we have in this case.

The relevant Fifth Amendment protection reads:

...nor shall be compelled in any criminal case to be a witness against himself,

US courts have ruled that a criminal suspect/defendant may not refuse DNA testing based on their Fifth Amendment rights. However, the Fourth Amendment requires a warrant issued by a judge before a "search" can be performed.

US courts have ruled that (except for convicted felons and other narrow exceptions) police must obtain a warrant before coercing someone to give up a DNA sample.

However, based on the 1985 California v. Greenwood case, if you spit on the sidewalk, throw away a cigarette butt or lick a stamp, then legally you have "abandoned" the DNA and police can collect it without a warrant. California v. Greenwood focused on household garbage placed in bins outside your curtilage, but that reasoning was expanded to include "abandoned" DNA as well.

N.B., IANAL

Re:Sounds improbable

[NotSanguine]

Yet another good reason why you should never, ever talk to the police.

Re:Sounds improbable

[SourceFrog]

What if it's a false positive?

Also, for those who think this is extremely unlikely and automatically believe DNA evidence is some sort of slam-dunk:

Teenager wrongly accused of rape (and imprisoned) because of DNA contamination (fortunately, it was picked up in this case)

DNA evidence contamination leads to review of 7,000 cases The police in Victoria are reviewing 7,000 cases involving DNA evidence after they had to withdraw murder charges in a high profile cold case. Police now say they deeply regret having charged a man with the murders of Margaret Tapp and her daughter Seana, at their home in 1984. They charged Russell Gesah two weeks ago, but since then problems have emerged with the DNA evidence.

DNA rape sample procedures 'not adequate' Adam Scott, from Devon, was held for a couple of months after being accused of raping a woman in Manchester. The charges were dropped when it emerged a DNA sample had been contaminated at LGC Forensics.

Police Fear 'Serial Killer' Was Just DNA Contamination A notorious German serial killer known as "the Phantom of Heilbronn" might not exist. Police believe DNA evidence which pointed to a 15-year trail of crimes across Germany was a case of contaminated cotton swabs.

Aerosolized Vaccine as an Unexpected Source of False-Positive Bordetella pertussis PCR Results etc.

Re:Sounds improbable

[mark-t]

I said "legitimate" for a reason. By legitimate, I meant that the test was performed in an environment where factors that are not intended to alter the results do not affect them. Both procedural error and contamination are examples of such outside factors.

Re:Sounds improbable

[v1]

It's very hard to fight a confession in court. DNA evidence gives you a little bit better odds to escape justice.

He may have done it just to get it out of the way. Once they had his father and his son's DNA on file, it wouldn't take long for them to be knocking on his door, that alone fingered him. He may have decided it was more pleasant than the inevitable long and public fight to get his dna and get the legal ball rolling.

And there are some other possibilities. He might have been high when he committed the murder, and honestly had no firm recollection of the event and didn't believe he was guilty. Or may have been psychologically repressing the memory of the event.

Re:Sounds improbable

[Solandri]

That's why the US has the fifth amendment (and why a right against self-incrimination is a good idea in general). Not turning in DNA is not probable cause for an investigation, and if that is why they started investigating him, the case would have a high chance of being thrown out

No, the fifth amendment just means refusing to turn in your DNA is not evidence of guilt. They can investigate whomever they want (which is why a lot of innocent people get arrested/convicted - overly aggressive detectives and prosecutors convinced that some WAG theory is correct, DNA or not). The cases which are thrown out for fifth amendment violation prior to trial are the ones where a suspect refuses to answer them / give DNA (i.e. legally invokes his fifth amendment right), and the investigators continue to cajole him until he relents and changes his mind.

If they systematically went over the records to find everyone who lived in the area at the time of the murder, used DNA to eliminate 96% of them, and concentrated their investigation on the remaining 4%, there wouldn't be a problem with that. If he refused or they weren't able to get a DNA sample from him legally, then they couldn't mention that to a jury as a reason that he's probably guilty. They'd have to convict him based on other non-DNA evidence, but that's how murder trials were decided for centuries.

Re:Sounds improbable

[Arker]

Please elaborate on how this is a good thing, because I'm really confused about it. To me it sounds like, the police finally found a way to identify a murderer, but then this 5th amendment thingy comes in and it gets thrown out on a technicality. What's good about that?

It's a mixed blessing for sure. Unfortunately it seems to be the best practical possibility. The idea with the 5th Amendment is to prohibit and thus prevent the Police from doing things they shouldnt do. Ideally, this could be seen as completely separate from the parallel task of convicting parties who have been caught and whose guilt is proven. This would mean that, if the police for example conducted an illegal search, and thereby found the evidence to put a murderer away, the murdere should be put away, the evidence should be used, but the policeman responsible would also be facing serious charges as well.

In practice, the courts figured out very early on that this simply is not practically possible. Police routinely put mutual protection (the "thin blue line" and "brotherhood" mentality) above their oath and above the law. Police almost never investigate other police. Police and prosecutors have to work very closely together and as a result prosecutors are *extremely* averse to investigating or charging policemen, no matter how clear their guilt. Judges are loath to cross police as well, even if less so, but Judges normally cannot do anything without the police investigating and the prosecutor filing charges anyway. So, in practice, police are above the law and cannot be held responsible for their crimes in any but the most unusual situation.

Acknowledging these facts, our courts fell back pretty quickly to a different position. If they cannot punish police who break the law directly then all they can do is remove the incentive that leads them to their criminal behaviour in the first place. Why do police perform illegal searches? To gain evidence, to secure convictions. So if you cannot directly punish them for doing this, what else can you do about it? Take away the incentive. If police know that any evidence they find will be excluded at trial anyway, they should no longer have any incentive to perform illegal searches. It's very sad when the result is a clearly guilty person walking away unpunished, but what is the alternative here? Even as-is, police still perform a steady stream of illegal searches, and evidence gets thrown out as a result now and then. But if the evidence wasnt thrown out, if it was allowed? If we took that route, the practical result would be that police would ignore and trample our rights with impunity anytime the whim struck them and there would be no practical motivation for them to behave lawfully at all.

Re:Sounds improbable

[s0nicfreak]

Perhaps they asked her family if it was her lighter. Or perhaps in that area lighters are not sold to minors (they aren't in my area, as ridiculous as that is)?

Re:Sounds improbable

[jafiwam]

You should watch the TV show "First 48". LOTS of moments like that on that show.

Also pounds home "they only catch the stupid ones" and "never talk to police"

Re:Sounds improbable

[jythie]

I think I have seen presentations like this... scary what can go badly even with absolutely no ill intent on the officer's part.

Re:Sounds improbable

[BLKMGK]

Have you got a source for this? The article simply stated lighter or did I miss something?

Re:Sounds improbable

[BLKMGK]

Crap, you're right! :-(

"The decision to launch the dna appeal came after De Vries in May broadcast information about a Playboy cigarette lighter found in Vaatstra's bag which contains dna traces that match the traces found on the schoolgirl's body."

I missed the last part. Why is the lighter even mentioned?

Re:Sounds improbable

[BLKMGK]

No, the DNA on her body is ALSO mentioned. They mentioned the lighter up front though and I missed the part about DNA also matching on her body. Apparently the fact that the lighter was sold locally led them to believe that the person was a local who did this - hence the mass DNA gathering. It would have been helpful had they spelled that out a little more clearly IMO but they DID mention a DNA match on her body that I missed...

Re:Sounds improbable

[Anspen]

I also wonder what Dutch law is as to the admission of DNA evidence in trial is. Is it enough to provide grounds for arrest, but not usable in court?

According to the media/the prosecutor, the DNA evidence (which was rerun after the accused was arrested) is not sufficient on its own, they will need either a confession or strong circumstantial evidence (proof he was near the scene of the murder for example).

Re:Sounds improbable

[BLKMGK]

At this point, unless he has confessed, it appears that the DNA is the only linkage...

Re:Sounds improbable

[Anspen]

True, however they also have test results from both his father and his son which would eliminate "simple" false positives such as mislabelling his sample. Beyond that, they ran a second test after he was arrested, presumably more accurate, Finally, they DNA evidence on its own isn't sufficient, that will have to get a confession or a more evidence. Which should be a lot easier now they have specific suspect.

Re:Sounds improbable

[Anspen]

The DNA evidence came from more than one sample. Some was retrieved from the body, but at least one sample came from a lighter found inside the bag of the victim. While the homogeneity in the area the crime happened is quite high, the DNA testing accounts for this (not to mention that there's still al lot of variation even between parent and children or siblings, let alone stranger, even from the same ethnic group.

Re:Sounds improbable

[Anspen]

The DNA from the lighter matched the DNA on her body, so not just "someone who onced touched a lighter".

Re:Sounds improbable

[Kittenman]

That defense only has a chance of working *IF* one actually has a documented twin.

Or even an undocumented one. :)

Re:Sounds improbable

[SourceFrog]

The most likely explanation is that the DNA sample that they believed came from the assailant just happened to be at the crime scene for any of a million other reasons.

Reading the article, all it says is that traces were found 'on the schoolgirl's body' and on a lighter. So even if we take it face value, at worse it seems to "prove" that he might have been there for some reason ... e.g. maybe had a smoke with her and possibly sex ... that doesn't prove murder. They could've shagged, he could've left, and someone else could've murdered her.

The strange thing about this case is that they were probably more likely to be looking for a match on a relative. Due to the similarities in the DNA of relatives, this seems like a sneaky way to effectively get your DNA against your will (e.g. if you have one brother and your brother 'volunteers', your brother is effectively 'volunteering' your DNA as they can detect a sibling match) ... that doesn't sound morally legitimate to me, seems like it would violate the 4th amendment or something if it were in the United States, I think.

Re:Sounds improbable

[yndrd1984]

The *ONLY* way you can get a 100% match with a false positive with a legitimate DNA test is if the subject has an identical sibling.

Too bad they don't do a 100% test. I've never heard of any law enforcement organization even trying to do complete genome sequencing, and I'm not sure if that would do any good since any real-world sample of evidence is going to have at least some kind of contamination.

Re:Sounds improbable

[SourceFrog]

The DNA on the lighter matched DNA from the rape itself

That would either prove they had consensual sex (assuming 16 is legal in the Netherlands), or it proves he raped her, but how does it prove he murdered her? That couldn't possibly have been someone else, after they'd done having sex?

Re:Sounds improbable

[crackspackle]

I do agree that police need to be careful with DNA evidence and not use it as proof of guilt where it implies no such thing, but that does not seem to be the case here.

You can't even say that for sure here. I've played with a cigarette lighter before and the one thing I recall is I quickly rubbed my thumb raw. Needless to say, a lot of DNA came off in the process. If the girl did use the lighter after him, that could easily explain his DNA embedded in her fingers, but the fact it would have ended up on her fingers could explain it ending up a lot of other places too. Ever rub your eyes, blow your nose, scratch your crotch or wipe your ... well, you get the idea. Who knows what the girl did with the lighter or what she did afterwards either.

Add to that, the guy is 44 years old and has never committed a crime nor even been a suspect until now. Granted, he was 31 when the crime occurred but he was quite old even for the type of behavior required to commit such a brutal crime to come to the surface. The fact nothing is known of him since would make it even more unusual.

Re:Sounds improbable

[pipedwho]

A more likely reason for the DNA being on the lighter was that the rapist started the conversation with the Dutch equivalent of 'do you have a light?'. And then everything snowballed from there.

So the inference that the rapist lived locally is still specious.

They may as well have just assumed the crime was committed by a local in the first place, and started their dragnet on pure probability of locality (based on the likely fact that far more locals inhabit the area than non-locals).

Re:Sounds improbable

[mark-t]

If the twin is undocumented, then the defense only works in fiction.

Re:Sounds improbable

[chrismcb]

To me it sounds like, the police finally found a way to identify a murderer, but then this 5th amendment thingy comes in and it gets thrown out on a technicality. What's good about that?

Because they didn't actually find a way to identify the murder. That is what is wrong with that.
If you ask everyone if they did it, except for one person. And they all said "no". Does that mean the last person did it? Ignoring that someone might lie, you are assuming the murderer is one of those people.

Re:Sounds improbable

[joaosantos]

I read somewhere that there are already databases with DNA profiles collision between unrelated individuals, I bet the probability of a collision in a such a small region is astronomically higher.

Re:Sounds improbable

[tehcyder]

The DNA matched DNA found on a cigarette lighter found in her schoolbag - not DNA from the rape itself apparently. It's possible in my mind that the guy is innocent of rape\murder and guilty of selling a schoolgirl a lighter or her guilty of stealing it. More details need to come out, this isn't "solved" in my mind unless they have DNA evidence from the rape itself that matches.

Wow, you really ought to offer your services to this poor guy as a defence lawyer, almost certainly the prosecutors haven't even considered these alternatives..

Re:Sounds improbable

[tehcyder]

Why is it ridiculous to not sell lighters to minors, if smoking is illegal for them? The number of other reasons you need a lighter are few and largely implausible for a child.

For any case I can think of, the child could borrow the lighter from an appropriate adult. And, no, minors do not have equal rights to adults. Sorry.

Re:Sounds improbable

[tehcyder]

The DNA matched DNA found on a cigarette lighter found in her schoolbag - not DNA from the rape itself apparently .... More details need to come out, this isn't "solved" in my mind unless they have DNA evidence from the rape itself that matches.

Especially when they're admittedly going on a fishing expedition through the entire town. There is no doubt that there would be other peoples DNA on her personal belongings. Probably several peoples DNA from various places. This is exactly the kind of thing people are afraid of when they don't want their DNA in a database.

Yes, because obviously what happened is that the girl was raped and murdered, and there was no DNA evidence from that, but there was on the lighter, so this guy is going to be convicted solely on the basis of his DNA being found on this lighter which he couldn't possibly explain away otherwise.

Re:Sounds improbable

[tehcyder]

Same thing has been going through my mind. The guy may never have met the girl - he may have dropped the lighter in the road, and she found the shiny thing lying in the dirt and picked it up. Girls of all ages like shiny pretty things.

So - they've located a guy who touched a lighter that the dead girl had in her possession. Now, it's time to do some real police work, and figure out what that means, IF ANYTHING.

Fuck me, Sherlock Holmes posts on slashdot! With your unerring logic you have shone the clear light of reason on the feeble attempts by police to solve a horrible rape and murder. Brilliant.

Now you just need to explain how the same fucking DNA was also found on the victim's body.

Come on, I know you can do it. I expect she accidentally brushed her knickers against a bush where he had been wanking off earlier, eh?

Re:Sounds improbable

[Runaway1956]

BLKMGC managed to make me feel stupid, without being hateful. Oh well - you're free to hate, go for it.

Re:Sounds improbable

[bp m_i_k_e]

The article, itself, states: The decision to launch the dna appeal came after De Vries in May broadcast information about a Playboy cigarette lighter found in Vaatstra's bag which contains dna traces that match the traces found on the schoolgirl's body.

Re:Sounds improbable

[BLKMGK]

Yes, went back and reread it and spotted what I'd missed - mentioned it below. The mention of the lighter threw me, I didn't understand why that was important. However since it was apparently being sold in that town around that time it was used as evidence that the person who commited the crime was likely local and thus supported the DNA requests.

Re:Sounds improbable

[SkunkPussy]

How do you propose to carry out 1 million DNA tests that are all legitimate by your definition of legitimate?

Re:Sounds improbable

[dgatwood]

Or she could have sat in the same chair.

DNA is highly circumstantial evidence by itself. In the absence of means and a motive, it should not be enough evidence to arrest anyone, much less convict someone.

Unless, of course, that DNA was found in meiotic form inside a body cavity, in which case it is much less circumstantial.

Re:Sounds improbable

[s0nicfreak]

1. The number of legal reasons a minor might use a lighter far outnumber the illegal reasons.
2. Minors are not always with adults, nor should they be. Please do not use "child" to mean all minors. A 17 year old is quite different from a 2 year old, for example.
3. There are already laws against minors smoking. There's no need for an additional law that doesn't even impact minors smoking (any minor that can illegally get cigarettes can easily light them).

Real life example: When I was 15, I was in college and cooking for myself. One day I returned home to find the power was out. So, I could not cook dinner unless I lit the stove manually. I was out of matches. So I went to the store, only to discover I could not buy matches nor lighters.

Privacy issue: DNA dragnets

[concealment]

I don't like the idea of DNA dragnets.

Just because I'm a male within 5km of a rape does not mean I should be required to give up my DNA.

First, who owns it? Does it get destroyed? Do I trust government to do that competently? No: it will be sold to the highest bidder.

Second, am I coerced into doing this? Will they shame me publicly for not giving up my DNA?

Finally, who else knows about it? Is my health insurance going up because they've found I'm susceptible to lung cancer or AIDS? What if there's a way to tell if I'm gay or prone to alcoholism (hic)?

There's got to be a better way to solve these rapes than asking all of us to give up private information at the threat of arrest.

Re:Privacy issue: DNA dragnets

[SJHillman]

Assuming you're referring to this article in particular, let me define the most important word in the summary.
volunteer/välnti()r/
Noun: A person who freely offers to take part in an enterprise or undertake a task.
Verb: Freely offer to do something

If you're referring to some possible future event that may or may not happen and is vaguely related to this, then please disregard.

Re:Privacy issue: DNA dragnets

[h4rr4r]

Who said anything about being it being required?

Did you not notice the less 100% participation rate in the summary?

This was totally voluntary. If you do not like their answers to your questions you don't give it. Now stop karma whoring and read the fine article.

Re:Privacy issue: DNA dragnets

[Anonymous Coward]

These are worries that I would have as well. In the UK there has been a history of abuse by the police of DNA samples that they have taken in such situations, now they're permanently on a DNA database that is very hard to get off.

However the database cannot be used by any other entity such as an insurance company. The database holds markers too, rather than doing a full genome deconstruction. Problem is, that's today's policy, and databases have a history of being sold when a bidder comes along offering the right amount at a time the seller needs the money, regardless of the people's wishes within the database.

The idea of the dragnets is that hopefully a relative of the criminal will volunteer the information, and thus the real criminal will be caught as a result. Nobody expects the real criminal to actually volunteer the information!

Re:Privacy issue: DNA dragnets

[samuX]

well your concerns are good but i think that instead of fighting the idea to give your DNA you should pretend that the dna will be used only for that investigation, that any information will be destroyed afterward and that - no matter what - it will be used against you from health insurance corp.

Re:Privacy issue: DNA dragnets

[dsnbaka]

This was a voluntary search. There was no mandatory need to give your DNA.
See it as a last effort to resolve the case and it was done because the DNA matching techniques have improved so that if a match in the family is found the search can make the connection to a small group (family) and search from that point further.

Re:Privacy issue: DNA dragnets

[Anonymous Coward]

I am not the OP, but what would have the police done if the murderer had not given his DNA? They'd have a much smaller pool of suspects on which to focus. What would life have been like for the 10% who did not volunteer?

Re:Privacy issue: DNA dragnets

[crazyjj]

But when does it stop being voluntary? It's voluntary now. But a few cases like this will make it very tempting for lawmakers to move to the next level (making it mandatory for particular areas in particular investigations). And from there, to making it mandatory for the entire citizenry. And from there, to including scans for potential diseases in the database (for the public health, of course). And from there, to insurance companies wanting access to that info....and so on. Pretty soon you could be in a Gattaca type situation.

Not saying this is going to happen, or that one step necessarily has to follow from the previous. But you have to understand why this particular slippery slope makes a LOT of people VERY nervous.

Re:Privacy issue: DNA dragnets

[Sydin]

If you'd taken the additional ten seconds required to actually read more than just the headline, you would have stumbled upon the fact that nothing was "required" of anybody. It was strictly on a volunteer basis. In some countries, and I know this is a shock to those living in the USA, governments still consider people innocent until proven guilty. These people were being asked to provide assistance to their police force in order to catch a rapist, and the vast majority chose to do just that. You'll notice that there's nothing stating the 10% who refused are behind bars right now, and that's because deciding NOT to turn in your DNA due to privacy or other such concerns does not instantly make you guilty of suspicion. The anti-government, anti-police stance on this website rivals that of a Ron Paul fanclub forum. Protip: Not all cops are corrupt, and not all governments want to slam a boot down onto your face forever.

Re:Privacy issue: DNA dragnets

[L4t3r4lu5]

Here's another word for you:

Definition of COERCE 1: to restrain or dominate by force
2: to compel to an act or choice
3: to achieve by force or threat

"Give us your DNA so we can catch a rapist" fits definition 2 pretty well, don't you think?

Re:Privacy issue: DNA dragnets

[benjfowler]

DNA is not so useful for pinning evidence on somebody (many people can share the same fingerprint, however unlikely). However, if there is a mismatch between your DNA and the one found at the scene, the likelihood of it being you is effectively zero.

DNA is better for ruling people OUT than putting somebody in the frame. Following from this, it's entirely rational to volunteer a DNA sample, because it puts you out of the frame without a shadow of a doubt.

Re:Privacy issue: DNA dragnets

[crazyjj]

Problem is, that's today's policy, and databases have a history of being sold

Or being hacked and used for even more nefarious purposes.

Re:Privacy issue: DNA dragnets

[cryptolemur]

It's not that slippery a slope. At least, where I live, neither DNA collected for any research purpose or fingerprints for passports can not be used in criminal investigation, no matter what. That's the law.
Now, it can be argued that the law can e changed anytime "the government" feels like it, but then again, by the same logic the law could also be changed to require everybody to wear AV-recording devices 24/7 at the convenience of "the government"...

Re:Privacy issue: DNA dragnets

[medv4380]

There really ins't a better way. DNA really is our only answer to the issue of Justice in relation to sever crimes like Rape and Murder. People are falsely accused of Rape and Murder all the time, and occasionally we find out about it. Hopefully before we put them to death or destroy their lives. The end goal it to make it so that you cant do those things without getting caught. It's got to the point were Rapists have been doing things to reduce the chance of their DNA being present. Which also reduced the odds that a Rape would result in a child since I don't know of any way of a child being conceived without leaving some DNA behind. If you believe that Rapists are a result of bad genetics taking advantage of sexual reproduction to gain a marginal reproductive advantage then they are weeding themselves out. Ether they use protection to avoid detection, or they don't and they get caught. That along with free morning after pills for rape victims and you'll see a drastic decline in the people willing to Rape others. Murder is a bit different but if we get to the point where premeditated murder is unheard of, and are left only with crimes of passion then I'll be satisfied with the results. As bad as Rape and Murder is punishing Innocent people is much worse. DNA alone shouldn't convict, but it is a very good start. You're argument of "There's got to be a better way to solve these rapes than asking all of us to give up private information at the threat of arrest." is also a Red Herring. No one in the article was threatened with prison time for not volunteering their DNA. If you're stupid enough to commit a crime, and then submit your DNA voluntarily to be checked against said crime You're a Moron and deserve the Darwin Award. What they were hoping for was a Parent, Child or Grandchild to donate their DNA to help narrow down the list of possible suspects. Their was always the possibility that the suspect was already dead, or not stupid enough to submit his own DNA.

Re:Privacy issue: DNA dragnets

[menno_h]

Actually, the local chief of police said they wouldn't (on a show on national television). The chance of one of your relatives submitting DNA is so large that they'll be able to arrest you if you are guilty, even if you didn't give them anything.

Re:Privacy issue: DNA dragnets

[93 Escort Wagon]

Spot on.

BTW I feel compelled to point out this happened in the Netherlands, which is often held up as an example of European Enlightenment (TM) to be contrasted with a perceived lack of freedom in the United States.

Not that I couldn't see this exact scenario play out in exactly the same way here.

Re:Privacy issue: DNA dragnets

[menno_h]

People were concerned about this, but the desire to get this case solved was stronger than any worry about the DNA.

Re:Privacy issue: DNA dragnets

[Anonymous Coward]

Doesn't that mean those of you saying we shouldn't volunteer are coercing us too? I'm going to fight coercion by volunteering my DNA to the police...

Re:Privacy issue: DNA dragnets

[digitalsolo]

Not all cops are corrupt, and not all governments want to slam a boot down onto your face forever.

Absolutely true, but in the US at least, corruption exists in any police force of appreciable size such that I would not generally trust any police force in this country. Many police OFFICERS are great people. One of my best friends is a cop, he's a great guy. I still would not trust his department as a whole. FWIW, the largest infractions I've ever committed is downloading a few songs and speeding on occasion. I'm not a criminal in any real sense of the word.

Re:Privacy issue: DNA dragnets

[crazyjj]

Health insurance? We pay for that via our taxes, so there's nothing to increase individually.

Being gay? Nobody gives a fuck.

Are you certain both of those things are always going to be true? Because that database could be around long after attitudes shift and government policies change.

Re:Privacy issue: DNA dragnets

[cryptolemur]

Exactly! This is pretty much what the paternity tests do -- they can rule out paternity 100%, but only give a "good possibility" of fatherhood.
I gather the police will have to have other lines of supporting evidence, too. Which, I assume, are easy to come by if the guy did it. There will be inconsistencies in his story, places he shouldn't have been, places he should have been etc.

Re:Privacy issue: DNA dragnets

[rhsanborn]

Not here. I was fingerprinted to run it against the FBI database to make sure I didn't have a previous record. I couldn't get employment without that background check. The FBI put my fingerprints in their system, and now, will have them as a reference. Of course, I shouldn't have anything to worry about, since I don't plan on doing anything wrong. Fortunately, no one was ever put in prison on circumstantial evidence ...

Of course, the FBI isn't interested in making a DNA database of people not convicted of a crime.

Re:Privacy issue: DNA dragnets

[coldfarnorth]

Yes, yes, you can copy and paste from a dictionary too.

This is no more compulsion than saying "I'll pay you $5 to mow my lawn" compels you to do break out the lawn mower.

Anyone could have said "No thanks" and that would have been the end of it, so no, definition 2 does not fit.

Re:Privacy issue: DNA dragnets

[tibit]

You mean, like they don't give a fuck in France these days, for example?

Re:Privacy issue: DNA dragnets

[MacGyver2210]

Just because I'm a male within 5km of a rape does not mean I should be required to give up my DNA.

Nobody 'required' him to give his DNA. It was simply requested.

Re:Privacy issue: DNA dragnets

[martijn hoekstra]

I don't like the idea of DNA dragnets.

Just because I'm a male within 5km of a rape does not mean I should be required to give up my DNA.

First, who owns it? Does it get destroyed? Do I trust government to do that competently? No: it will be sold to the highest bidder.

I suspect the police of gross incompetence, but not this level of organised malice. Besides, I doubt there are many high bidders on the black DNA market.

Second, am I coerced into doing this? Will they shame me publicly for not giving up my DNA?

No, but you could be under closer scrutiny in the investigation. Which IMO is not a good thing, but it is debatable.

Finally, who else knows about it? Is my health insurance going up because they've found I'm susceptible to lung cancer or AIDS? What if there's a way to tell if I'm gay or prone to alcoholism (hic)?

No

There's got to be a better way to solve these rapes than asking all of us to give up private information at the threat of arrest.

One would think so. So far, in this case, they have been unable to come to a breakthrough through other means.

Re:Privacy issue: DNA dragnets

[Lennie]

That was hardly voluntary.

This is a small community where a lot of people know each other and knew who did go to collection point.

This probably falls in the category of peerpressure.

The police also had a list of people and people who didn't volunteer would be visited or called by the police to ask why.

Re:Privacy issue: DNA dragnets

[andywebs]

I know the usage of (sic), what does (hic) mean?

Re:Privacy issue: DNA dragnets

[jythie]

'freely offers' gets kinda hazy when social pressure is involved.

Re:Privacy issue: DNA dragnets

[jythie]

The implication is that 'no thanks' wouldn't be the end of it, either through social pressure/suspicion or through the police giving extra scrutiny to locals who did not participate. Even without the police, the whole 'we all gave our DNA.. why didn't you? what are you hiding?' can be a powerful thing.

Re:Privacy issue: DNA dragnets

[jythie]

Ahm..... there have been issues with government institutions giving personal data to other institutions, both public and private. So not exactly 'paranoid'.

Re:Privacy issue: DNA dragnets

[Anonymous Coward]

Second, am I coerced into doing this? Will they shame me publicly for not giving up my DNA?

In the Netherlands neither suspects nor convicts are allowed to be named (and thus no shaming either). Only the first name and first letter of the last name of people who are convicted are usually released to the press. Although in high profile cases leaks do occasionally happen.

Re:Privacy issue: DNA dragnets

[jythie]

That might be the cultural difference here. In the US, many people do not trust their local police for a variety of valid historical reasons...

Sure there are demographics in the US who view the police favorably, but to many they just want to stay off the radar because just being noticed can be life destroying. They do not see the police as a force that is there to help their lives, but a force generally used against them, or at minimal one that is sufficiently powerful and unpredictable that they are best just avoided.

Plus.. you don't need all cops to be corrupt for people to feel uncomfortable, just enough.. and more importantly, a culture where corruption and poor behavior by cops is not dealt with by LEO in general. It isn't the individual cop people worry about, but how many forces in the US handle problems within their ranks.. so there is a feeling that if a corrupt cop or official does come into play, the larger law enforcement community will side with the bad apple rather then help the 'civilian'. There are plenty of good cops, I would wager most are good people.. but as a group they tend to protect the bad cops before they protect people FROM the bad cops, and that makes dealing with them risky... a risk that can be significant depending on who you are and how good your resources are.

Re:Privacy issue: DNA dragnets

[ottothecow]

Same here--I'm pretty sure I got placed into the database when I got my digital fingerprints taken as part of a background check for an internship at the Federal Reserve. I would have preferred not to provide them but that was the only way to get cleared for the area I wanted to work in.

Shouldn't be any problem with a legitimate offence but its pretty hard to get incorrectly flagged for something when you aren't in the system to start with.

Re:Privacy issue: DNA dragnets

[HeckRuler]

But when does it stop being voluntary?

The point just before we whip out the Molotov cocktails and metaphorical pitchforks.
It's perfectly understandable for people to be nervous about this sort of thing. And rightly so. That little bit with it being voluntary makes a WORLD of difference.

The slippery slope argument is not arguing that we should go back, merely that we shouldn't go any further.

Also remember that GATTACA is a utopia. For most people.

Re:Privacy issue: DNA dragnets

[Cederic]

In the UK there has been a history of abuse by the police of DNA samples that they have taken in such situations, now they're permanently on a DNA database that is very hard to get off.

Which will be my reason for declining to participate in any dragnet in the UK.

If the police arrest me to force a DNA test, the shit will truly hit the fan.

Re:Privacy issue: DNA dragnets

[Kjella]

If you're stupid enough to commit a crime, and then submit your DNA voluntarily to be checked against said crime You're a Moron and deserve the Darwin Award.

Or drunk or high or on heavy medication or having a psychosis or having some other condition that causes you to have blackouts, maybe a multiple personality condition or some other mental illness or through some sort of denial process has managed to repress any memory of it to the point where you genuinely believe yourself you didn't do it. I remember reading about a case about a rapist that had been convicted before DNA evidence, he'd continue to insist on his innocence in prison and as DNA testing became available then he wanted his case reopened, volunteered a DNA sample and was acting like finally this horrible miscarriage of justice would be resolved - right up to the point where the DNA evidence nailed him as the perpetrator too. A guy told me about a one night stand where he didn't remember even meeting the girl until waking up in her bed next morning, too drunk to remember but according to her not too drunk to get it up so it's certainly possible to have sex without remembering, probably even easier on drugs. He might not have a clue he was turning himself in, stranger things have happened.

Re:Privacy issue: DNA dragnets

[robi5]

Yes, like posting on facebook and kindly ask the murdeder to come forth? Get real, man.

Re:Privacy issue: DNA dragnets

[benjfowler]

DNA fingerprinting doesn't collect information useful for determining whether or not you're susceptible to various diseases.

OTOH, if insurance companies found a legal way to cheat (because "cheating" is what it is) and get a blood sample, and sequence your genome, then they could just refuse to insure potentially unprofitable customers, defeating the entire point of insurance -- that of pooling risk -- in the first place.

Re:Privacy issue: DNA dragnets

[spire3661]

Most are good people, but EVERY cop i have ever known personaly breaks the law on a daily basis for his own benefit. I dont understand how they keep thier mind from shearing.

Re:Privacy issue: DNA dragnets

[coldfarnorth]

I'm sorry, "all the cool kids are doing it", or "I'm really disappointed with you for not doing this" is not the same as compulsion. As others have already mentioned, this was occurring in a fairly small town, so the odds of one of your family members contributing a sample and incrimination (or exonerating) you is fairly high, regardless of your decision.

Just to clarify one thing:

If you have to make a decision where choice 1 results for more (subjective) unpleasantness for you than choice 2, that doesn't mean that you are compelled to chose choice 2.

The world's full of trade-offs, and if keeping your DNA in your own pants is worth a little Q&A with the police, then be prepared to do that. If they come after you with a $5 wrench, I agree that it's moved in to coercion, but putting up with a little pointed questioning . . . put on your big girl panties and deal with it.

Re:Privacy issue: DNA dragnets

[coldfarnorth]

That was hardly voluntary.

This is a small community where a lot of people know each other and knew who did go to collection point.

This probably falls in the category of peerpressure.

O. M. G. Not the peer pressure!

The police also had a list of people and people who didn't volunteer would be visited or called by the police to ask why.

Citation needed. I'd actually bet that they don't give a shit. Mostly because they figure that at least one of your relatives will volunteer a sample which will in all likelihood exonerate you.

Re:Privacy issue: DNA dragnets

[SourceFrog]

Assuming you're referring to this article in particular, let me define the most important word in the summary. volunteer/välnti()r/

You don't understand how DNA works. If you have a brother and your brother "volunteers", congratulations, your brother has effectively "volunteered" your DNA (as it's possible to detect sibling matches, as well as other relations). That rather stretches the definition of "volunteer".

It's unlikely the police even expected 100% match here - they were more likely looking for a relative match.

Re:Privacy issue: DNA dragnets

[Schz]

With regards to your first two questions, by all means mistrust the government to the highest level convenient. I can answer (mostly) your final question. As of right now, with our current level of genetic analysis technology, it is not possible to determine anything useful from the tests employed in these situations aside from the degree of likelihood that it matches another sample. This isn't a safeguard set in place against the fears you named; it's a coincidence coming from the tools we have with regards to cost, ease of use, and most importantly, speed. What these tests try to find is short, predictable lengths of DNA through a variety of different methods--it's by no means a full DNA sequence. Furthermore, the location of these lengths of DNA isn't determined, only their presence and how many of them are found in a single sample, so it would be impossible to determine if they were part of a known gene. That's as of now. Our ability to fully sequence DNA samples gets better yearly.

Re:Privacy issue: DNA dragnets

[mdielmann]

The whole premise of what I'm reading in your post is that rape and murder have more than a genetic predisposition, but that it is as guaranteed as eye color. I've heard no indications that this is the case, so I don't think them wearing protection is going to be the ultimate gift to mankind that you suppose it is. Moreover, I'm sure we can find a number of cases where the rapist or murderer was able to have multiple sexual encounters that were consensual and resulted in children, so this "evil gene" could still be passed on even if he was "practicing safe rape". That kind of negates the whole point of your argument.

You're argument of "There's got to be a better way to solve these rapes than asking all of us to give up private information at the threat of arrest." is also a Red Herring. No one in the article was threatened with prison time for not volunteering their DNA.

No, of course not, but you're completely ignoring peer pressure, which does have a lot of research to back up its existence and power, in inluincing people to "volunteer". So, would you want to be the one guy on your block that didn't submit a sample? Do you imagine it would make you a little uncomfortable? Then there's the whole "this worked so well, if only we could require people to do this every time" scenario, which isn't farfetched, and then we will have people being imprisoned for refusing to "voluntarily" give a sample.

Re:Privacy issue: DNA dragnets

[medv4380]

The whole premise of what I'm reading in your post

Learn to read. My whole premise is directed at the wingnut and screwloose presenting an argument that states DNA should never be used. If his argument was anywhere near sound then it would be wrong to do DNA testing on anyone, even a clearly identified suspect in any case. In my post I choose the words I did for very simple reasons. When I stated "If you believe that Rapists are a result of bad genetics" I'm leaving that entire Genetics part up to the individual. I'm also not ignoring "peer pressure" because the OP was more hung up on this being forced by the police with the "Threat of Arrest", or did you fail to read the OP that I was responding too. Peer Pressure might be a valid argument as to why the Idiot submitted his DNA, but it doesn't make him any more or less of an idiot. He could have easily sided with the 4 to 10 percent that choose not to submit their DNA. As long as none of his family submitted they may have concluded that the perp was dead or a drifter. However, I don't care about his reason for submitting his DNA, and if someone is trying to argue about the accuracy that is for a Lawyer to fight out in a court room. I'll be happy when the DNA testing is a full sequence test, but until that is cheaper and quicker I'll settle for what we can do rather than advocate for doing away with it like the OP is suggesting. As for myself If I had the money I'd have my DNA sequenced and analyzed even if I wasn't asked to, but the test I want is a full sequence test so I can have it for myself. If someone asked for a Rape or Murder I'd gladly volunteer because as much as people might complain about false positives DNA has got more Innocent people out of Jail to justify it. DNA alone isn't enough to convict, but it is a good starting point.

Re:Privacy issue: DNA dragnets

[tehcyder]

Assuming you're referring to this article in particular, let me define the most important word in the summary. volunteer/välnti()r/ Noun: A person who freely offers to take part in an enterprise or undertake a task. Verb: Freely offer to do something

If you're referring to some possible future event that may or may not happen and is vaguely related to this, then please disregard.

On slashdot everything's a slippery slope.

Re:Privacy issue: DNA dragnets

[tehcyder]

I feel compelled to point out this happened in the Netherlands, which is often held up as an example of European Enlightenment (TM) to be contrasted with a perceived lack of freedom in the United States.

People outside the US don't generally perceive you as having a lack of liberty. It's the absence of equality and fraternity that disappoints us.

Re:Privacy issue: DNA dragnets

[mdielmann]

Why on earth would I believe the genetics questions you brought up had anything to do with your parent post when he doesn't mention that once? He mentions other people using it for DNA screening (valid, but unlikely), and selling data (also valid, not sure how likely), but not as a way of ending the racist gene. Also, given the collision rate of current DNA tests, almost anything is better than violating a bunch of people's privacy, stigmatizing some individuals, and having data that is probably going to be used incorrectly. Perhaps you don't value privacy that much, but I and a number of other people do.

Basic Statistics...

[Anonymous Coward]

"The percentage of people participating was closing in on 90%" OR "The percentage of men participating was closing in on 90%"? This is why people typically botch circumcision rates, pregnancy rates, etc. Normally the question only applies to around half of the population. Of course, if the police are attempting to use the info to find family members, then "Dutch police asked 8000+ men" should be "Dutch police asked 8000+ people" (after all, something on the X chromosome could be relevant, too.)

Sample Size

[Jamu]

I wonder how big the sample size would need to be to get two 100% matches.

Re:Sample Size

[Chrisq]

That depends. If he had an identical twin it would be much smaller than would be needed anyway. There are also more and less usual combinations. Also if he were (for example) the only Native American immigrant within a 5km radius it would probably need a much larger sample than if he was of indigenous ancestry.

Re:Sample Size

[coolsnowmen]

(in addition to the identical twin comments), the change of collision drastically changes depending of the type of DNA comparison test being performed. Usually this is a function of how many allele's they are testing for.

Re:Sample Size

[2fuf]

two identical twins?

Re:Sample Size

[chispito]

I wonder how big the sample size would need to be to get two 100% matches.

As few as two people, I should think.

Re:Sample Size

[j-beda]

Regardless of the underlying theoretical limitations of the science, there are also operational limits to the process - there are non-zero chances of people mislabeling samples, mistyping data and misreading results. Presumably one runs multiple tests on any positive match, but knowledge of the expected results has also been shown to influence the conclusions that DNA analysis technicians make.

Filling your database (fingerprint, ear print, tattoo, DNA, etc.) with info from people unlikely to be guilty does increase the odds of a false positive, which of course wastes investigation resources and potentially can convict the wrong person and allow the guilty to stay at large.

Really?

[Walterk]

It seems rather unlikely to me that if you committed a crime you would volunteer into giving your DNA in this sort of style. Was it a full match or just based on a few key metrics, which seems the most common form of testing? It could be family of him, for instance.

Don't jump to conclusions

[sideslash]

We have to be careful treating technology like this as an infallible oracle.

- Technicians could have made a mistake.
- Our understanding of the science of genetic matching could be flawed in ways that we haven't come to realize yet.
- The guy could have had consensual relations with the girl (creepy though that is) and somebody different murdered her.

It's strange that he volunteered a DNA sample. Hopefully that's just because most criminals are dumb, and not because he's being wrongly accused.

Re:Don't jump to conclusions

[DeathToBill]

And since the sample was found on a lighter in her bag, "consensual relations" here might mean, "Hey, mister, got a light?" "Sure, keep it." He might be guilty of abetting under-age smoking, nothing more.

Re:Don't jump to conclusions

[Spamalope]

- The guy could have had consensual relations with the girl (creepy though that is) and somebody different murdered her.

While (very) unlikely, maybe the guy had a drunken one night stand and doesn't even realize she was the murdered woman. He wouldn't know he had a reason to avoid giving a sample.

While it's very likely that he did it, it can be fun to invent a few alibis. Just after he left her boyfriend arrived, caught her cleaning up, figured out what she'd been up to and killed her in a jealous rage. Her drug dealer settled the score for her unpaid debts. He'd followed them home and waited until this guy left so he could catch her alone.

Re:Don't jump to conclusions

[TheP4st]

FTFA: The decision to launch the dna appeal came after De Vries in May broadcast information about a Playboy cigarette lighter found in Vaatstra's bag which contains dna traces that match the traces found on the schoolgirl's body.

Re:Don't jump to conclusions

[HeckRuler]

Pointed out elsewhere:
" ...cigarette lighter found in Vaatstra's bag which contains dna traces that match the traces found on the schoolgirl's body. "

Re:Don't jump to conclusions

[robi5]

> It's strange that he volunteered a DNA sample. Hopefully that's just because most criminals are dumb, and not because he's being wrongly accused.

How is it not already a dumb move, to say the least, to kill someone?

Re:Don't jump to conclusions

[sideslash]

I agree with that in a moral sense, but not all murderers are dumb in an IQ sense.

Re:Don't jump to conclusions

[tehcyder]

Nobody's treating the DNA evidence as an "infallible oracle". It's only geeks who would think otherwise.

Re:Don't jump to conclusions

[tehcyder]

And since the sample was found on a lighter in her bag, "consensual relations" here might mean, "Hey, mister, got a light?" "Sure, keep it." He might be guilty of abetting under-age smoking, nothing more.

And the DNA on her body?

No, you'll have to change it to "he offered her a light, then had random, consensual rough sex, after which he walked away and someone else entirely came along and murdered her." Or it may be that the rapist/murderer was his jealous wife, who stole a used condom after he fell asleep one night and planted the DNA. I'm fairly sure I've seen a film where that happened.

Re:Don't jump to conclusions

[sideslash]

It's human nature to want your witch hunt to successfully root out a witch, and it's human nature after the huge endeavor of analyzing DNA from all those people, when they've found a match, to say "let's prosecute". Hence the arrest instead of just an interview. I don't know the truth of the matter, I'm just suspicious.

Case Solved ?

[slb]

I doubt a court has already given a verdict. An element of proof like DNA (even if it is a very strong one when properly retrieved) is not enough. A tribunal has to review these elements first to exclude errors.

The DNA test was remarkably accurate

[Arancaytar]

The makers guaranteed that the rate of false positives was only one in 8000. :-P

Solved?

[The_Noid]

Everybody in the Dutch talks as if the man is convicted already. He's not. The case is not solved until a judge has had the last word, and given the inaccuracies in DNA matching I'm very interested in what a judge has to say about this.

Re:Solved?

[jiriw]

Everybody in the Dutch talks as if the man is convicted already.

Ok .. this is so untrue...

This is the news article from the major Dutch online newspaper. Put it through Google translate if you don't trust my translations:

nu.nl

AMSTERDAM - A suspect has been apprehended in the 'Marianne Vaatstra' case. The Procesution Councel (PC) confirmed it this monday morning.

...

The Justice dept. will not reveal any details for now. The PC and Frysian police force will hold a press conference 18:00 CET in Drachten.

...

The Dutch Forensics Institution (NFI) is currently performing a minute double-check of the identity of the suspect.
"For both PC and police force it's of major concern we only submit an official statement to the press when it's certain the identity of the suspect is confirmed without question by the NFI."

...

Moreover [the spokeswoman of the PC] emphasizes DNA will 'never be enough', "there always will need to be more evidence".

Re:Solved?

[jiriw]

And of course you shouldn't trust my translations. The 'spokeswomen of the PC' actually is the spokeswoman for the NFI.
Still it's very clear from all articles I read from 'decent' press resources, the DNA evidence will never be the sole evidence a suspect will be convicted upon. However it is enough evidence to arrest a suspect. There already were clues the suspect had to be local. This DNA search wouldn't have happened in the first place if there weren't.
All tests were done voluntarily. Of course that doesn't exclude social pressure. If that has influenced the suspect to hand over his DNA, we'll only know when he, or his (either chosen or assigned) lawyer says something about it. It doesn't help to speculate about that now.
That such a large part of the population submitted his DNA doesn't surprise me the slightest. Here in the Netherlands there is still an amount of trust between the peoples and the officers of the law. And material like this ever being handed over to private parties (like insurance companies) is unfathomable. Also there are some good privacy regulations in place. Some politicians (especially those of right-wing parties) would very much like them relaxed but.. for now they still hold... most of the time. What we (the Dutch) should take care about is not voting politicians into office that would like to abolish such regulations. Because that would turn things for the worst like it did in some other first world countries where there is no more trust between people and 'the law'.

DNA database

[Anonymous Coward]

In Sweden we have the PKU-registry. Anyone born after 1975 has a DNA sample taken from them at birth, however it can only be used for your own treatment, identification of remains or research. So far they have kept their part of the promise of not letting it be used for criminal prosecution. Even tho as some would like it to be included in tools available for the police.

Re:96%

[Arancaytar]

You can swab my tongue when you wrench it out of my cold, dead, mouth.

Re:Please tell me...

[MyLongNickName]

I agree with you. But if the DNA match sperm on the girl's body, then it is pretty damning. You are right that an investigation should take place, but it is hard to explain outside of some type of consensual relationship and the guy not coming forward originally to help the investigation.

Why didn't he move?

[Anonymous Coward]

I don't understand why did this guy not move out of the area years ago? I guess it just goes to show that most criminals really are stupid.

Re:Idiot

[Jesrad]

Assuming the person arrested is not guilty, it could just be a false positive match. DNA tests are not 100% precise, in fact I read they are 99.7% precise only, resulting in approximately 1-in-300 errors, so in any wide-ranging tests with thousands of different DNAs all coming from the same area (meaning most of them had a lot of common ancestors across them) it was almost bound to happen. Imagine the uproar if TWO 100% matches had been found (and I do not mean homozygote twins) !

Note that roughly 1 in 10-15 person has more than one set of DNA, through chimerism - rare - or plain mosaicism - which is much more common than usually thought: that's part of how you can get "surprising" results of >10% paternity tests turning out negative in countries where those tests are sold over the counter. There are documented cases of botched criminal cases due to this, the most famous being Linda "I'm my own twin" Fairchild's.

And if he IS guilty then it may be one way to work up doubt into a future jury, using precisely those arguments. So, it's not necessarily idiotic.

Re:Idiot

[Nocturna81]

Actually: they found him because a family member of his gave their DNA...

Re:Solved? Not quite.

[MeepMeep]

I know this is breaking the rules, but I've read TFA. The DNA sample was found on a lighter in the girl's bag next to her body.

Not just on the lighter

From TFA:
" ...cigarette lighter found in Vaatstra's bag which contains dna traces that match the traces found on the schoolgirl's body. "

Re:Idiot

[Nocturna81]

Never mind...the TFA is different then my recollection of the case on the radio..

Mod parent up

[crazyjj]

That's a VERY important point in this case. People hear "DNA" these days and automatically think "irrefutable evidence." But in this case, it's just further evidence--NOT ironclad proof of guilt.

oblig tsa reference

[Anonymous Coward]

you do realize people "voluntarily" let their children be molested (oh, the irony in context of article) at airports in this country, right?

sadly, I don't think there is a line anymore - we have truly become sheep who will do whatever big brother tells us regardless of cost ($ or rights) or lack of benefit...

I seriously doubt the reaction at fbi, nypd, etc is envy ("oh, if only it weren't for that pesky constitution we could do this!"), more like embarrassment that one of the most liberal countries on earth beat them to it...

Re:oblig tsa reference

[s0nicfreak]

IMO it's only molestation if the person doing the act enjoys it sexually. Otherwise you could say parents "molest" their babies every time they change a diaper.

Re:oblig tsa reference

[viperidaenz]

molestation has nothing to do with the person performing the action. It has everything to do with the person the action is being performed on.

Re:oblig tsa reference

[tehcyder]

you do realize people "voluntarily" let their children be molested (oh, the irony in context of article) at airports in this country, right?

In the context of the article, which is about a raped and murdered schoolgirl, your comment is not so much ironic as grossly distasteful and hyperbolic.

The patdowns at airports are only sexual molestation in the eyes of paranoid autistic types, who are of course heavily represented on slashdot, and for whom bodily contact is both frightening and rare.

Re:oblig tsa reference

[s0nicfreak]

So you're saying... babies are molested every time their diaper is changed?

Re:oblig tsa reference

[viperidaenz]

Stop being a retard.

Re:oblig tsa reference

[s0nicfreak]

Seriously though, I have no idea what you meant.

Re:oblig tsa reference

[viperidaenz]

Scenario: Person A grabs Person B's ass.
Outcome 1: Person B enjoys the ass grabbing, happy times follow
Outcome 2: Person B is outraged and disgusted by such an action and Person A gets in trouble.

Re:oblig tsa reference

[s0nicfreak]

Many people that were molested as children enjoyed it - or at the very least saw nothing wrong with it - at the time.

Re:Please tell me...

[MyLongNickName]

You missed the part in the article where samples were found on her body as well.

Re:Please tell me...

[MyLongNickName]

Here is the relevant text

"The decision to launch the dna appeal came after De Vries in May broadcast information about a Playboy cigarette lighter found in Vaatstra's bag which contains dna traces that match the traces found on the schoolgirl's body."

Re:Solved? Not quite.

[DeathToBill]

Ooops. Still, inaccurate information on /. - who'd've thought?

Prosecutor's Fallacy

[McGregorMortis]

I haven't RTFA, but from the summary, this sounds like a textbook example of the http://en.wikipedia.org/wiki/Prosecutor's_fallacy, which is a special case of the http://en.wikipedia.org/wiki/Base_rate_fallacy

If you have a suspect in hand, then DNA evidence can be pretty compelling. But when you comb through the population trying to find a suspect using DNA evidence, then you're walking straight into a miscarriage of justice.

Re:Prosecutor's Fallacy

[photon317]

No mod points today, but it sounds like you're right. Deep link to specific example that sounds exactly like this case: http://en.wikipedia.org/wiki/Prosecutor's_fallacy#Multiple_testing

Re:Prosecutor's Fallacy

[coldfarnorth]

There are a few more details that make the Prosecutor's Fallacy less applicable to this situation. First, they are looking at a relatively small population, so the odds of two unrelated matches is lower than if you were scanning a database of millions of profiles. Second, they have a pretty complete picture of the population that they are searching, so duplicate matches can be investigated. Third, this is all just evidence at this point - the trial is yet to be carried out. Assuming that a miscarriage of justice is going to occur because large quantities of DNA evidence was used seems a bit harsh for this early in the game.

Re:Prosecutor's Fallacy

[robi5]

Riiight. Police can work with one set of evidence and confirm it with a DNA match, but not the other way around. Sounds logical. Probably the Dutch police / justice system does not employ even one person who is a statistician. They should come straight to Slashdot if they want to have a clue and just release the raper already.

Re:Prosecutor's Fallacy

[robi5]

Mod parent up, finally someone who can step away from the shallow dismissive "thinking" that characterizes 90% of posters here.

Re:Prosecutor's Fallacy

[mdielmann]

First, they are looking at a relatively small population, so the odds of two unrelated matches is lower than if you were scanning a database of millions of profiles.

From what I've read, the reasoning for the small area is that the lighter was sold nearby. While that increases the probability the person lived there, it's no guarantee. So, the question is more, "what are the odds of someone visiting having a duplicate match", rather than "what are the odds of two locals having a duplicate match".

Re:96%

[crazyjj]

No kidding. I need to pretty rock-solid assurance that the sample will be destroyed and removed from the database after it's checked. And a "we promise" from some yokel cops ain't gonna cut it.

Re:False positive?

[Meneth]

I've heard it's about 1 in a million, per sample. So for 8000 samples, it would be 1 in 125. Good enough for an arrest, I think, but not for a conviction.

Re:Please tell me...

[MozeeToby]

How about bad luck? Its not like the police do whole genome sequencing to identify suspects, there's nothing that says you couldn't have markers similar enough to someone else to get flagged for a crime you didn't commit. Even if the accuracy were 99.99999% you'd have 700 people in the world who match, and I highly, highly doubt their accuracy is that high.

Exactly

[Anonymous Coward]

If government is involved, there is no "volunteering". The threat of physical force is ALWAYS present with government, no matter how far under the carpet they sweep it, or how much smokescreen they blow in front of it.

Re:Exactly

[Anonymous Coward]

A few years back, the TSA had just started requiring people to put their shoes through the X-ray scanner, but it wasn't completely mandatory yet. At one airport, we were informed that we didn't have to take off our shoes, but if we didn't, we could be subject to additional security. Needless to say, everyone "voluntarily" took their shoes off. If there's a punishment for not complying, it isn't voluntary.

Re:Exactly

[guises]

Wasn't this the reasoning behind the "enhanced patdown" procedure? To get more people to go through the nudie scanners? I recall the head of the TSA said this explicitly.

Re:Exactly

[Incadenza]

Here in the Netherlands there is. It is unlawful to take anything from your body without your consent. Material taken without your consent cannot be used as a proof. A couple of years ago they tricked somebody into a friendly chat at the police station, including a cup of coffee on the house. Afterwards the cup was sent to the DNA lab for all the DNA traces he had left on them! End result: the guy was set free, because the proof was unlawful.

So why only ask the men?

[91degrees]

so that the murderer could be traced through (close or distant) family members sharing part of this DNA.

This seems reasonable, but confusing. If they asked the women as well, then even if he didn't volunteer his, there would have been a good chance of his daughters volunteering. Each would have had a 50% match indicating a parent or a sibling.

There must have been a good chance of the perpetrator not having a living father, and having no brothers.

Re:So why only ask the men?

[rve]

They looked at the Y chromosome first, which is identical (barring random mutations) between men who share the same male ancestor, because women don't have a Y chromosome, so it does not get recombined in the offspring.

Re:Idiot

[jones_supa]

Maybe the TFA is wrong and your recollection was correct.

Re:Idiot

[GodfatherofSoul]

This happens a LOT; especially with police searches. Many criminals think refusing to concede to a search is a sign of guilt, so they volunteer to be searched even when they're carrying a weapon, drugs, etc. Happens all the time in those cop documentaries.

Re:Idiot

[tibit]

It must be understood that DNA tests are not comparisons of the entirety of the genome. They are just hashes, and very low bit-count hashes at that (16 to 24 bits I'd think). Worse yet, they are not hashes of the entire genome, just of small parts of it. Feel free to correct me if I'm wrong, of course.

Re:Idiot

[deadboy2000]

Assuming he's guilty, maybe he simply realized that taking responsibility for his actions was the right thing to do.

Re:Please tell me...

[tibit]

Well, the sentence "DNA is never a 100% match" is really meaningless. What is being tested, usually, are some markers present in the DNA -- it's like taking a hash of a very small fragment of the file (the genome). Once you have a suspect, you can the do some sequencing and do much better comparisons where it's then out of the question that the DNA is from given person (or his/her genetic twin). I agree it still shouldn't make you anything more than a suspect, though, and must be insufficient on its own for any conviction other than a misdemeanor IMHO.

asked?

[slashmydots]

So they "asked" people to submit their DNA instead of demanding it. Now if you were the actual perpetrator, wouldn't you say "no" instead of submitting your DNA? Yeah it'd make you look guilty but so does a 100% DNA match, lol.

Re:Didn't work as expected

[HeckRuler]

You want my DNA? Come back with a court order.

As is perfectly your right. If it were any other way, it wouldn't be voluntary, now would it?

And you're right, this did not work as expected. But it worked. So there's some cheering going on.
Br. Me though? That little bit in there with it being voluntary makes it just SO much better that I might consider it. (They destroy all the samples and data afterwards, right?)

Reverse double thinking

[ai4px]

The guy probably gave his DNA knowing full well that they wouldn't expect the suspect to provide it... and therefore the authorities would look at anyone who didn't provide a sample. They fooled him by doing what they said they'd do, eh?

Re:Reverse double thinking

[mark-t]

Actually, no... the original intent was evidently to try to find somebody who might be related to the perpetrator. The only way they could do that is by actually testing the DNA they received, which might narrow their results down to people related to the best matching results.

They got 100% match though... which, coupled with multiple testings, is going to be pretty tough to dispute, unless you have an identical twin.

The suspect probably didn't expect there to be a 100% with him.

Re:Solved? Not quite.

[avandesande]

How much DNA could be on a lighter? Sequencing a hair seems to make sense but how can you separate the miniscule amount of DNA that several people could of handled?

Statistical error probablility?

[flyingfsck]

People react as if DNA analysis is infallible. I seriously doubt that. Given enough volunteers, there is bound to be a false positive eventually. It could very well be this poor sap.

Re:Statistical error probablility?

[tehcyder]

People react as if DNA analysis is infallible. I seriously doubt that. Given enough volunteers, there is bound to be a false positive eventually. It could very well be this poor sap.

That is why you don't convict people on DNA evidence alone. If this guy ends up in prison, it will be because a lot of other evidence points to his guilt. p. There is no such thing as 100% reliable evidence, otherwise there wouldn't be any real need for trials.

A Dutch clinical biologist called me in his office

[fonske]

to negotiate on the price for our One Lambda monoclonal antibody against HLA-B27.
It was not a clinically interesting antibody for him since he had a high prevalence of cross reactivity with another HLA antigen in his lab and this was well documented by St Catharina Ziekenhuis in Eindhoven.
Translation: The Dutch seem to inbreed in their own kin so much that the most mutating gene in the human genome had such a high frequency that the "monoclonal" antibody par excellence was worth jack sh*t in their labs.
Corollary: They will need to sequence quite some loci on the Dutch genomes to make inferences on the DNA sample being unique.

Sperm and hair

[Frans Faase]

In another news message it was stated that his DNA matched with sperm and a hair found near the victim. That makes it sound a little different.

Re:Idiot

[Cederic]

At least one study agrees with you:
http://link.springer.com/article/10.1007%2FBF01542085?LI=true#page-1

Found in a field

[Frans Faase]

The victim was found in a field along the road to her home. She had celebrated Queens Day in a disco and was biking home. Sperm was found on her body and she had a cut in her neck. A closer examination revealed that she was strangled with her own bra. DNA found on a cigarette lighter in bag matched DNA found on her body, suggesting that the person who killed her, was someone she knew. Google translate of Dutch fact article.

Terrifying

[ThatsNotPudding]

Anyone who thinks any police force would dump / not test the samples of the 8,999 innocent men are fools. Make no mistake; this won't be the only stone-cold whodunnit that 'miraculously' gets solved in this burg. Every case will be rapidly moved along to airtight frame-up all thanks to CSI: Eyedropper.

Re:Terrifying

[tehcyder]

Anyone who thinks any police force would dump / not test the samples of the 8,999 innocent men are fools. Make no mistake; this won't be the only stone-cold whodunnit that 'miraculously' gets solved in this burg. Every case will be rapidly moved along to airtight frame-up all thanks to CSI: Eyedropper.

If teh evil government wants to do an airtight frame-up of some of these "innocent" men, why would they need the DNA to help them?

Re:96%

[robi5]

Riight, it'll be so straightforward for you to verify that rock-solid assurance, I see how you'll become convinced. All these police investigations are so transparent anyway, and of course there is no value at all in retaining your and thousands of others' DNA for future investigations of murder.

The real argument here

[cfalcon]

Is to not give your DNA out. Sure, one possibility is that this guy decided "well, whatever, they won't catch me", and gave his DNA with the assumption that the test couldn't POSSIBLY work. That's possible.

The article discusses this as if it were fact. What if this is a screw-up? What it was his DNA there for a different reason? I mean, what's the confidence on these tests? Everyone is taught in school that everyone's DNA is unique, but our ability to test doesn't magically do a file-diff, and there's room for error. It doesn't go on for seventeen digits of significance or anything, and with thousands of dice being rolled, who knows?

What about the possibility that this guy gave his DNA knowing that he didn't do it?

I know we shouldn't underestimate the stupidity of criminals, but it seems pretty dumb to give your DNA when the police come around looking to convince you, especially when you could claim non participation for a NUMBER of reasons (or just sell everything over the course of the over a decade this took, and leave for somewhere else). His actions were of a man who believed he was innocent.

Just change the tone

[ub3r n3u7r4l1st]

Donate your blood, get $100!

Then extract the DNA from the blood samples....

The Implication

[Nirvelli]

The show "It's Always Sunny In Philadelphia" covered this subject a while back, sort of.

Does not apply here

[rve]

I find this method seriously scary due to the probability of a false positive. I mean, suppose you have a system that only fails once in a million times and the killer has already left the country. You ask the two million people in the metropolitan area to submit DNA. You get on average two matches. One doesn't have an alibi. You take him to trial and tell the jury that he not only doesn't have an alibi, he had a 1 in a million DNA match. It sounds pretty convincing. It is very possible the jury won't have the understanding of statistics to ask "was this a sweep or did you only test a couple of likely suspects?" Nor is it likely that the information will be volunteered by the court.

The one in a million false positives would apply if you took a million random, independent samples, it does not apply in this case.

First of all, this wasn't a 'DNA profile' they took (this was tried a decade ago and had no result), but a Y-chromosome match, intended to find male relatives of the killer. If matches were to be found, further circumstantial evidence would then be used to narrow the search down, and finally a full DNA profile would be taken to positively identify the killer.

There was circumstantial evidence that the killer was someone the victim knew, and probably lived within cycling distance of the crime scene. They didn't randomly test millions of people, but planned to test 8000 men who were between age 15 and 60 at the time, and lived within a roughly 2 mile radius of this rural village.

Need to take care

[ewibble]

Care needs to be taken when using global database searches to match DNA, otherwise even if you have only a slight chance of a false positive the chance finding someone who is a match is quite high, because your population is quite high.

see http://www.ted.com/talks/peter_donnelly_shows_how_stats_fool_juries.html (from 10 min) not specifically about DNA but the same principle. also
http://www.guardian.co.uk/commentisfree/henryporter/2009/may/25/dna-database-false-positive

Re:Bzzzt! Thanks for playing, try again.

[Cederic]

Yeah, I just couldn't be bothered caveating my example. Sorry.

Re:Please tell me...

[SourceFrog]

"traces found on the schoolgirl's body."

Which could mean he sneezed on her. I took that to imply 'semen' though, but even then, it doesn't prove murder.

PCR

[Ultracrepidarian]

I'm still waiting to see the first frame-up through the use of a little kitchen PCR work. A good science fair project?

Re:citation needed

[raynet]

"Only if you consider monozygotic twins and use the uncited wiki as a source." says anonymous coward and continues without citing any sources :)

In reply to many of the comments and OP

[SkyLeach]

While it is true that government databases identifying the DNA of every citizen would reduce crime and increase convictions, it also means a great many other things. Here are two of them.

1.) Police would get very lazy very quickly. DNA would be used as the "de-facto" proof of guilt, in spite of the fact that DNA is shed by everyone all the time. An ex boyfriend gets accused of rape and since his DNA is there he's automatically guilty. A store gets robbed and the man who hasn't bathed in a week gets charged because his DNA is the "most prevalent" around the register. He probably should have used Dial.

2.) Just because our government is mostly benign now doesn't mean it will always be that way. When social and economic upheaval occurs a great many things can change. Imagine, if you will, a government run by neo Nazis. Suddenly they have DNA proof of, not only the Semitic groups, but all of their offshoot genetic cousins as well. Or perhaps someone develops a gene targeted disease and gets their hands on the government database. for my closing, one word: Gattica.

As to the man accused of rape in the Netherlands, I am curious if he was just trying to play innocent, trying to turn himself in, had forgotten about the rape, didn't think of the incident as rape at all, or if he is innocent and somehow got his DNA involved through some other means than direct collection from the victim. After all, it does seem a bit moronic to give one's DNA if one has committed rape (or any other crime) and hasn't been caught.

Some background

[DogPhilosopher]

I live in the Netherlands and have been (casually) following this case, so here's some background that might be relevant:

Some posters here wondered why this guy agreed to give his DNA. There is some evidence that he is mentally ill: in 2009 he was convicted of stealing a neighbor's car and joyriding while under the influence. He claimed not to be in control of his actions at the time, and that he only came to his senses while in the car. A psychiatrist diagnosed this as a dissociative fugue at the time (he was still convicted). A neighbor of his also recently stated that he has mental problems. So it's quite possible that he doesn't even remember the rape and murder. It's also quite possible that it's simply a lame insanity defense.

I think one of the reasons for this DNA-dragnet was that the area is sparsely populated, and the cities/villages there are tight-knit communities. Many people there are blood-related, so the odds of finding a partial match should be good. It may also be the reason that so many people were willing to participate; they wanted to believe that the perp was an outsider (some still think so). My guess is that some social pressure was involved as well. Anyway, I don't see something like this working in the major cities. Very few people would volunteer, and chances of finding a relative of the perp would be much lower.

Also, there were other DNA tests before, these were done to rule out two suspects - asylumseekers from Iraq and Afghanistan, respectively. They had been fingered in an anonymous letter, possibly with a racist motive. Analysis of the DNA found on the victim pointed to a caucasian anyway (not uncontroversial).

Misuse

[katiamp]

In a perfect world, full of rational, just and sound-minded people, I would agree with you - but then it would be a world without those crimes, anyway... Unfortunately, it's fairly easy to foresee some misuse of that kind of information. People in power have a way to turn these things against people they don't like - be it the Homeland Security agent using his/her job to snoop on and persecute an ex-spouse, or the TSA agent using his/her job to get away with fondling people and stealing small stuff. If "they" have samples from everyone, and you disagree with them or cross their path somehow, who's to say a bomb won't show up with traces of your DNA? Years ago I would read this comment and crack a joke about tinfoil hats, but in these days of FBI grooming homeless people to frame them as terrorists... well, it just doesn't sound funny anymore. :(