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Are Fingerprints Unique?
MattJ writes "There's an incredible article in LinguaFranca about fingerprints. Maybe they're not all unique after all. And maybe those fingerprint experts are not much more scientific than handwriting experts. Fascinating details."
Maybe O.J. was innocent....
If they fingerprints fit, maybe we'll acquit.
haha..
very funny..
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OS/2 - because choice is a terrible thing to waste.
This could mean many more convicted criminals are not really guilty? Oh the lawyers will have fun with this one! They are already trying to get people out of prision, but now they have even better evidence. This could end up costing the court system lots of money to retry thousands of cases, most of which probably shouldn't be retried.
~~Apathy alert: Approaching the Point of No Concearn
What can I say? I've seen them all and man they're all the same.
Sorry.
Dan
kinda like Bush and Gore...
better that 1000 innocent people be convicted rather than 1 guilty person go free
Facsinating details, but nothing conclusive.
There's always sufficient, but not always at the right place nor for the right folks.
To guestimate, I suspect the real numbers are about 10^12:1 false matches, which is quite alarming, if there are 10^7 entries, one in 10,000 will be a false hit with someone totally at random. The false negative rate is probably closer to 1% and might be as high as 10%.
Does anyone have better numbers, after all, I'm just guessing at this point.
--Mike--
The article goes on about how the assumption that no two prints are identical haven't been proven. This is of cource rather obvious, this statement cannot be proven, it can only be strengthened by failing to falsify it.
There is never any proof that is 100% watertight (other than in mathematics and other formal logic systems). The legal system will always have to settle for reasonable proof.
If an investigator picks up a suspect and his prints happen to match the perps, then you will have a hard time to prove you didn't do it. But remember it must also be proven that the prints that were found are indeed the criminals.
It's wery unlikly in my view that the fingerprint matching is ever the weakest link in the chain of evidence.
Puddin' Head Wilson was wrong. Bad Mark Twain!
The Blaster Master Fighting for Truth, Justice, and Evil Pie since 1979
Well fingerprints although not unique as we once though still provide good evidence. I remeber reading somewere that about 1 in 10,000 people have similar fingerprints. they still would be crucial evidence if the over 100 people with the same fingerprints in the country never set foot in the city.
Great. We're trusting a multi-variable analytical computer system that's as old as Pac Man... Especially considering that:
and
I could just picture the conversation in the lab at Lockheed International Conglomerate:
"Richard, I've been thinking...what about distortion from pressure on either the latent print or the test print, or both!" "Oh Sam, you know we only have 640KB of RAM to do our matrix multiplications in...and besides, the government's paying us a lot for this. We're gonna have one hell of a Christmas bonus..."
Consider this, too:
Great, they may as well be dowsing for water wells now... Okay, I bet $10 that the feebs' computer (AFIS) is a total fraud. The burden of proof, however, is on you...
This sucks. I'm going back to bed.
In 1999, marijuana killed 0 Americans...
Ewige Blumenkraft!
The software is available (in every police station), the data is available (also in the police stations) -- let's just see what the percentage of cases where the programs claim that the figureprints of two different people are the same.
The question is not whether fingerprints are globally unique -- as the article points out, given enough detail, they most certainly are, like all natural things.
The question is whether any two fingerprints differ enough for a smudged, low-detail, partial impression of a fingerprint to reliably match the one and not the other.
That is where the science ends and the craftsmanship begins.
For instance, at my work we use an Iris scanner to get into the building. That isn't useful for forensics, but for access to restricted areas........ Just imagine if you had finger prints almost the exact same as someone who had unrestricted (fingerprint) access to Nuclear Weapons. Bit of a strech, but it could happen.
Now, I'm not sure just what the accuracy is in the scanner, but let's assume for a moment that it's the same as "1 in 10000" that's being tossed around for fingerprints in this discussion.
At the same time, assume that the pattern of someone's Iris and their finger prints aren't linked in any way.
Combine the 2 and you've got a 1 in 10 billion chance of having duplicate records.
Dark Nexus
Dark Nexus
"Sanity is calming, but madness is more interesting."
Uh.... if i take your assumption of 1 in 10,000 people having similiar fingerprints, lets start assuming...
,Liechtenstein(32,207), or Bangladesh(129,194,224). But you may be referring to Botswana(1,576,470), or Estonia(1,431,471), or Swaziland(1,083,289). Or go to http://www.infoplease.com/ipa/A0004389.html to find out for yourself.
a) That's 7,322,564 people in New York,NY (1990 US Census) with a rate of 1/10,000 gives approx. 732 similiar ones give or take a variance of 1/x^2, whatever x being. Maybe as many as 1000, as few as 500.
b) That's further assuming we discount all the transient workers coming into town & all the tourists. Which may double the population on a given day. A population doubling due to this would not just double the "similiar score" to 1464, but would be something on the order of, hmm... 732^2, or 535824. Wow.. half a million, because this is combinitorial. Suzie Q182 matches 1464 other fingers, and each of those 1464 other fingers have thier own set of 1464 matches, but not with 100% overlap. False positives tend to blow up.
In fact, you could prove that someone out there has two fingers that are similiar to another persons singular digit. I'm not sure how to finagle the numbers to find out if the two fingers would be rated as similiar or dissimiliar. There probly is a secondary rate preventing a person from having two matching fingers.
Now for some more fun, you give the assumption that "if the over 100 people with the same fingerprints in the country never set foot in the city" to determine what country your talking about. (all figures are Bistro-Math(tm), please don't nitpick, instead create your own cosmology)
100 people times 10,000 is 1 million plus a bit for the guy with the finger that lives in the town. Well, you don't live in Albania(3,490,435)
Basically, a rate of 1/10,000 is scientifically un exceptable. And since there is no "rate" since all mistakes are due to technician error, not error in the system (can you say Cult?) there is no way for it to be a science.
USA-Democracy is 270 million YESes and NOes a day, not one every four years.
...look up the April 1999 issue, crypto fans. It contains an article about "The Voynich MS", a book (we THINK it's a medical textbook) from the Renaissance that NO ONE has been able to decypher. Solve this one, and you'll have one doozy of a line in your resume (and maybe, we'll find out something really neat in medicine!) Oh, yes, the illustrations are way-kewl, too: wild flowers, Terry Gilliam-style plumbing, and LOTS of naked women. The translation project has been on the net since 1991, and is WAY underpublicized, so I'm throwing this in to help out. Good Hunting!
teleny, friend of cats.
Damn, my fingerprints aren't unique, my ideas aren't unique... at least my Slashdot nickname is completely unique.
Phew, I feel better!
-N
The point of the arguement is that Finger Printing as it now stands can never be conclusive. It currently falls into the pseudo-science realm with astrology, dowsing, and advertising. In such that; if you do it wrong, you must not be doing it right. That the lack of falsifiability (ouch) is what raises science above the snake-oil, ponzi-schemes and Presidential Elections. It is equally interesting about the dogmatic zeal which FPEs defend thier core tenants. Perhaps more proof that: cognitive ideas = k, and that we are only redistributing them to reach the least entropic state. Kinda like a society wide protien fold of group thought. Better folding = more prosperous society, etc. Hows that for psuedo-science?
USA-Democracy is 270 million YESes and NOes a day, not one every four years.
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He did not say the FBI center, he said local LEO.
In many states, you get printed each time you are arrested.
Just by using an old set vs a new set for one suspect, you could then get a "Z" reference to other prints.
Since I have been printed 4 times in the last 5 years ( Professional Certffication and background checks) , I can tell you that the TX DPS has different imprints on my fingerprints and that they do differ. My girlfriend's prints are slowly disappearing, she's an EPA lab chemist. That in itself generates a "Z" factor. So there is a basis to run a true comparison test to determine the APIS DB's accuracy in matches.
Reality is just a clever Hack, and the Planck constant is the refresh rate.
The attempt to prove that a non-existant creature does not exist is what is known as an unfalsifiable statement. There is no possible way to prove that a non-existent being does not exist.
The correct approach in science and in philosophy is to start with a falsifiable statement (such as "Unicorns exist"). The more scientists and philosophers search for evidence of the existence of unicorns and fail, the more likely it becomes that unicorns do not exist.
have a day,
-l
I needed to be fingerprinted before they would give me my green card, what fascinated me was this machine they took my fingerprints on.
At first glance it looks like a photocopier gone haywire, with a largish monitor. This is where your fingerprint image gets projected. There are several squares of different sizes, and they look similar to the glass partition of an everyday photocopier.
No ink involved, He just asked me to lightly place my fingers on the glass, and he held my fingers at some points to keep them from jiggling (he was very exacting about it).
When he was satisfied, he brought the images of my prints up on the screen in front of us. He remarked "Well, no life of crime for you". He was referring to the fact that I had "excellent patterning". He remarked that "You have excellently defined fingertips" etc. etc. He then showed me the neatest thing he magnified my prints to the point that he could COUNT the skin pores between the whorls of my thumbprint
Actually I was impressed, since up til that point it had always involved me getting my fingers full of that stupid ink and having to roll them around on a piece of paper. That machine was much cooler.
And for the record, I don't have one :)
spam, spam, spam, spam, e-mail, news and spam.
Folks, rememeber the OJ trial? There we saw DNA evidience, based on modern science, with proven error rates and a far lower possibility of subjective reading, being totally rejected as forensic evidence. And yet, many people are locked up every day on the basis of fingerprint evidence, based on 19th century science, with unproven error rates and based entirely on subjective judgement.
Does anyone else see a double standard here? And how can we help society to make better, objective scientific judgements, rather than just listening to demagogues?
Information doesn't want to be anthropomorphized. -AC
I remember taking a tour of the FBI headquarters in DC when I was a kid. They had a picture on the wall of two guys. One of whom had been mistakenly arrested for a crime the other (it turned out) had commited. They arrested him, because his fingerprints matched the ones at the crime scene. Turned out that the two men had identical fingerprints (or near enough).
The nice people at the FBI made it sound like this was a 1 in a billion chance (which, technically, would make it so there are 6 other people out there with the same finger prints as me!), and that it was a freak thing. I'm inclined to agree with that.
So could I control the conditions in the womb with some large degree of accuracy and create a large group of people with strikingly similar fingerprints. Take 'em to court and have the assumption summarily thrown out.
This is yet another example of poor science© It has almost become the case that science means wearing a white lab coat while stating something as fact©
This is causing significant backlash©
The growth of psychic hotlines, faith healing and other panaceas is at least partly due to poor science© If the bar isn't held high enough that only science can qualify many other things can get through©
Here in New Zealand there was a prominant case of a boy with cancer where the boy's parents rejected traditional therapy and went with some quantum vibration panacia© The boy died a couple of weeks ago© Many people are blaming the parents, but could they have any way of rating one over another© Both treatments were applied by people who said they would work©
There have been many cases where medicine has shown use of poor science© There are diseases that people have fought for years to have the medical community investigate them, let alone accept their existance© Many people distrust doctors these days©
This effect happens in other areas© People have commented that all the major advances in physics occur after the previous generation of physicists die out¥I can't claim to actually know that is true however
Scientists' reputations are declining in this world© One day I would like to see Philosophy of Science taught early at school© When everybody is throwing information at you claiming they are facts© Everybody needs to be able to evaluate whether or not whether or not that information comes from a reliable method©
-- That which does not kill us has made its last mistake.
And I just found two identical snowflakes yesterday too!
As long as the people who fund voting machines and police labs don't understand what is necessary, the money for accurate scientific evaluations doesn't get allocated. And that comes ultimately down to scientific illiteracy.
It's ironic that the guy who likely will have to fix this, George "W" Bush, and his staff (including Jams Baker) have displayed such a stunning lack of scientific literacy themselves by proclaiming, without evidence, that "machine counts are more reliable".
No two fingerprints the same? Weeeeell... let's not get carried away here.
The (extremely valid) point here is not that fingerprinting isn't useful, but that it is by no means an infallible method. If you have a suspect and their prints could not POSSIBLY match the ones from the crime scene, then you can be pretty sure this isn't your man. However, to say that the main structure of the ridges of the two prints is exactly the same, that some of the secondary characteristics match, and that overall this is without a doubt a match.... that's kind of sketchy.
Developmental biology is far from the nice, linear-type science the public seems to believe it is... Certain attributes of the organism at any stage of it's development can be approximated, but it's not always as simple as "gene X is present, so phenotype (trait) Y will be expressed". The future of the "designer baby" where parents could pick and choose their child's characteristics is far, far in the future (even then it wouldn't be exact). Why? Because... genes are like a set of very general rules... it's chaos theory at it's finest. Here is a system that obviously has some underlying order (to produce an organism with 2 eyes, antennae, whatever), but even barring gross mutation, prediction of the final results of an organism's development is still (at this point) an estimate, at best.
It would be impossible to say exactly how many hairs a mouse would have, their precise location, and what color each would be by only looking at the genes of the creature. There's innumerable chances for deviation. You can stick two similarly colored mice together and say; "these mice are similar", but until you had an exact, infallible catalog of every minute detail of the organism, you would have no empirical (scientific) basis for saying how similar they are, or even "these mice are exactly alike". Even exactly the same genes (identical twins/clones) produce different results if you look closely enough.
BUT... that's a far cry from an objective justification for the impossibility of 'lighting striking the same place twice';P. The same 'proof' was used when "they" once said that no two snowflakes are exactly alike. Whiiiich... after someone did some serious, scientific researcg on the matter, later turned out to be bullshit;). Much in the same vein, "the identical twins had different prints" argument means jack; two people could have different sets of genes in respect to their fingerprints, exist in different environments, and it's still not impossible that they would end up with extremely similar (or even indistinguishable) fingerprints. There's a quite a few people in the world; see "Europeans descended from 10 males" a few days back... even though America's a large place, those ancestors have passed on a little bit to everyone with caucasian ancestry - that's a lot of people with the same daddies/similar genes;). Is it that hard to imagine that, even though the odds are extremely small, that two sets of prints, taken right off the two specimen's fingers, could be similar to the point that they would appear exact?
Now for the coup-de-gras... the fingerprints in crime scenes aren't lifted straight off someone's fingers in a controlled manner. There isn't some fingerprinting technician dipping the criminals fingers in grease and carefully applying them to the doorknob or whatever. As mentioned, smudging, processing, and method of extraction result in very loosely defined fingerprint specimens. Is it crazy to think that you can, 100% of the time, say with 100% certainty that "These fingerprints belong to this individual"? You bet. Should fingerprinting be forgotten, then? No, it's still useful, but... I think the courts have led people to believe that fingerprints are the end-all-be-all of forensic evidence. If America's going to claim that it's judicial system operates by "innocent 'till proven guitly", we might as well make the extra effort to make sure that the methods that we use to prove someone guilty are as sound as possible, or the system quickly becomes a farce.
Life: a sexually trasmitted disease that has a 0% survival rate.
DNA fingerprinting?
I demand a million helicopters and a DOLLAR!
Iff fingerprint matching is the only link in the chain, then fingerprint matching is the weakest link.
Iff a stronger form of evidence is added to a chain containing only fingerprint matching, then fingerprint matching is the weakest link.
Iff a stronger form of evidence is added to a chain containing fingerprint matching and any stronger evidence, then fingerprint matching is the weakest link.
USA-Democracy is 270 million YESes and NOes a day, not one every four years.
Look a little closer at my post again...
See? Up at the top there? The part where I said it isn't useful for forensics?
People should learn how to read and pay a bit of attention before they try to learn how to make witty or sarcastic replies...
Dark Nexus
Dark Nexus
"Sanity is calming, but madness is more interesting."
Even if you accept this figure of one in 64 billion the birthday paradox predicts that you can expect to find an identical pair of fingerprints in a database of sqrt(64e9) fingerprints which is just a little over 250,000. I believe the FBI fingerprint database is significantly larger than that. After this "threshold" of sqrt(N) is crossed the number of duplicates starts to rise quite sharply as the database size increases.
----
Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.
Iris scanners don't need a PIN as a hint or an index key to the database. There's apparently enough uniqueness, so you can compare the input with thousands of others and not get a false positive or negative.
Whereas with all the fingerprint scanners I've seen you need a PIN or some other info, so that the computer knows which record to compare with the biometric input.
This is for biometric access, not for forensic, but it should give you an idea on how relying 100% on partial fingerprint smudges really isn't a good idea.
Cheerio,
Link.
What is the point of this post? He states the obvious, then goes on to throw out some bullshit numbers that he admits are bullshit (and are wrong anyway (10^12/10^7 = 100,000)).
I don't mind the guy looking like a fool, but it wastes everyone's time when idiot moderators mod it up. "Huyuck, garsh, this guy posted numbers, he must be insightful!"
Bah.
Think of all of the tens of thousands, if not millions of cases that would have to be looked at again if it were happen. The resources for that simply don't exist.
Rich...
Ignore Alien Orders
IIRC, the reason the DNA evidence in the OJ simpson murder trial was unconvincing to the jury was because the defense proved beyond a reasonable doubt that the labs involved did not adhere to the standards necessary to proved that the correct sample had been analyzed.
The defense did not attack the concept of DNA analysis but the methods that were used in that particular case of DNA analysis.
And as bad as it is to possibly let a guilty man go free over a technicality, I would rather see the occasional guilty party go free than allow the police to abuse their powers with impunity. It was the LAPD that screwed up what was pretty close to an open and shut case.
have a day,
-l
The likelihood that something exists is quantifiable by a non-binary number (i.e. a percentage). The actuality of whether or not something exists is only expressable by a binary number (0 or 1, either it exists or it doesn't).
The likelihood (or probability) that something exists is directly proportional to the amount of evidence we have that that something exists.
have a day,
-l
I may be missing something here, but it would seem that there must be millions of points where fingerprints could be similar. Yet most police forces are prepared to accept 8, 10, or twelve points of similarity as being conclusive. If so then there, by coralllary, must be millions of points that are dissimilar. It would seem, in fairness, that the courts, or at least defence lwyers, should be looking for dissimilar points not similar ones. If there are six milion possibilities and I only match nine and am convicted it would seem that justice is a joke. So what's new?
Next, they'll say that hash collisions can happen. Whoops, I better fix all the code that I wrote, which was based on the assumption that it's impossible.
---
As copyright owner of this comment, I authorize everyone to defeat any technological measure which limits access to it.
This is easily verified with standard scientific practices. Grab 10,000 people and give them a metal ball and have them handle it for awhile (without telling them why), then grab clear fingerprint impressions. Give the balls to examiners whose job it is to grab as many fingerprint impressions as they can. Put all this into a database, then start pulling out fingerprints and having examiners match them up.
What is the error rate whereby fingerprints were matched incorrectly?
As I see it, the real problem is that people can only think in black or white. The focus of this little question has been if fingerprints are unique or not. The average person isn't mentally equiped to think in terms of "How unique are they?", a vast grey area. Science can never answer black-vs-white questions, but they can certainly measure grey.
Do paper cuts (especially big cuts) change the finger patterns? Just curious... :)
Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
That was the point. It was an attempt at humor.
-N
Our legal system is more and more trying to use gorge jetson way of dealing with their problems. They don't like explaining that they think a person is guilty. They want to say we found the prints we feed them in to the computer and our can the name of the defendant. Fingerprints don't lie and so he must be the one. This is wrong on many levels first My prints on a weapon says I may have touched it not that I killed anyone. Example I read where the FBI arrested a woman because a threat letter with "her prints" was sent to the Israeli embassy. All she had to do was load the printer or copier but that does not matter. It was found that she in fact was set up. But the embassy sent the letter to the FBI and the but it in there system and here name came out. When you think of it, it is very easy to frame some one this way. Second Partial fingerprints are just like other partial fingerprints. The pressure on FPE to get a name to spit out is huge. The FBI collects Fingerprints by the 100's of millions and one day you may find that it is your name the computer spits out. The reason FPE believe that they are full proof is because they what and even need to believe they are. As long as the system is believed to be full proof and once the computer spits out a name very little effort is put into finding any one else that may have done it. Push button police work is not good. But as long as the system can get away with it it is what we will get. Dont let any one have your prints if you can help it.
The problem isn't whether fingerprints are unique (although it's an interesting point that their uniqueness has never been proved). For all the author cares, they are unique. It's irrelevent to his chief argument.
The problem is that exact complete fingerprints aren't used in forensic investigation. Mere fragments are. And not just fragments; sloppy fragments, read by making impressions with the detective's dust and transfered onto paper. The question is therefore whether those fragments are unique relative to other fragments, given the additional fudge factor in how they're read, and whether the use of fragments instead of complete fingerprints is sufficient.
People need to work on their critical-reading skills.
-- Anne Marie
coup-de-gras
It's coup-de-grace. "Gras" means fatty or oily in French.
I'm sick of people misusing coup-de-grace. It means "stroke of mercy" and the term was originally associated with executions. For instance, in a firing squad execution the riflemen shoot the victim and then someone finishes off the victim with a coup-de-grace, that is, a pistol shot to the head. So it's not just a fatal blow, it's a humane act too.
sig semper tyrannis!
Suppose that there are N objects in the universe, and I've observed none of them. What's the probability that at least one of them is a unicorn? Well, given that I know nothing about the relative likelihood of Unicorn-ness among objects, the most likely a priori estimate of the likelihood of a Unicorn is given by quantifying across all possible predicates on the Universe, and computing the probability that IsAUnicorn(x) is true for some x. (After all, the IsAUnicorn predicate is just another predicate. I don't know its characteristic function, but it's got one.) Then it's easy: the Universe is finite, and so there are only finitely many predicates on it, and (drumroll please)...exactly one of those predicates has no elements!
So, our estimate of the probability that there exists at least one Unicorn, given that we have no evidence speaking to the question, either way, is 1 - 2^(-N), where N is the number of objects in the Universe. Thus, it is very, very likely that there exists a Unicorn, in default of any evidence -- but it is not quite certain.
If they can match a fragment of a fingerprint, that may be statistically provable to not be from your finger. However, doesn't each subsequent fingerprint or fragment thereof from another finger or fingers drastically reduce the chances of a false match?
Here in Perth Western Australia, There was a case involving a man from a local Aboriginal Tribe being accused of Statuatory rape of another member of this tribe. This girl had concieved and bore a child and DNA evidence was used as in the prosicutions case against the man that the child was his. The cort found however in such a isolated gene-pool DNA evidence was not conclusive.
-Jasa -- Linux - The SOURCE will be with you, ALWAYS
I agree that jails are merely almost isolated and very unhealthy social systems that reinforce the very worst behavior in both guards and prisoners. But isolation cannot teach anyone how to alter their behavior; it is used, sparingly, with children because a "time-out" gives them time to reflect rather than react. After childhood is over, the qualities of imagination and openness which make time-outs useful are almost always stunted, particularly in the types of persons who end up (justly or not) in prisons. I certainly would not want prisoners who had been held in complete isolation released into my society again after a "short" term!
We have learned a lot over the hundreds of years we have been locking up criminals, the insane, "delinquent" and "incorrigible" children, and other troublesome types. Unfortunately, we put almost nothing of what we collectively know into solving the problem of violent behavioral deviance. Why? The same reason we don't bother to raise children properly (at least paying attention!); nurse ill persons properly (that is, caring for them, trying to help them rest and sleep so their bodies can heal themselves); or teach properly: It's a lot of work! Hard work... work that requires love. (Love is an active, transitive verb -- seeking the good of the other; it's not some mushy emotion.)
Except in the case of violent offenders, the best technical solution for many crimes is probably an unbreakable monitoring bracelet and frequent supervision, with the offender remaining in touch with family, employment, etc. This is why the modern trend is to release prisoners into half-way houses before their sentence is completely over: They need routines, social contacts, a monitored transition into daily life.
Very interesting points in that article on how fingerprinting "became" scientific law. I questioned the whole validity of partial printing a bit but the general idea is solid IMO. You have a few sets of prints lifted from the crime scene. You run them through the data base at donut world and have Johnny FPE stare at them for a few hours, soon enough you have a match with some guy.. and he lives a block away from the crime. If there was a big world wide fingerprint data base and there was more than one match then you could eliminate the other people because they lived in different cities or continents. So even if by some coincedence that there is more then one choice you can deduce who is the culprit.
"I am a kernel in the linux army"
If you want to link fingerprints to a suspect you need to know that a fingerprint is unique (it is coming from him). Second thing you need to know is that his fingerprint is irreproducable (noone can fake it). Most people here concentrate (as asked) on the uniqueness. But...
A number of years ago, I saw a documentary about reproducing fingerprints, and for the EE nerds here: it's fucking easy.
Here is how you do it. You get the print from the guy you want to impersonate. Take some laserprinter toner. Take a soft brush, and wipe some toner on his fingerprints. They should appear in black. Then take some tape, and lift the toner from the object. Tape it onto a white sheet of paper. Scan the paper with the black fingerprint on it. Do some retouching of the image. Print the negative on sheet. You know have a sheet, with see-through where the fingerprint has to come. You can also take a photo of the lifted thumbprint, and directly use the negative. The result is the same. You make a singlesided PCB, using the sheet. Put some liquid rubber in the 'mold' (the PCB, which now has the pattern of the fingerprint). Take the dried up rubber, and voila: a rubber stamp, with the looks of a fingerprint. You can glue this thin rubber stamp on you own finger as well.
There goes the irreproducability of fingerprints
nosig today
They don't claim that fingerprints are not uniqe, and they don't claim that it's 'no more accurate that handwriting analysis'.
They simply claim that, according to principles of science, it is merely an *assumption* that no two fingerprints are the same. It is not a FACT.
They call into question not whether or not fingerprinting is of use, but whether or not fingerprint evidence should be taken as absolute. They cite the lack of an acknowledgement of an 'error rate', as any scientific method must have.
The point is, courts will jail people for life on fingerprint evidence, yet no modern (or historical) scientific study has *ever* been done to determine how accurate this is. No proper error rate studies have been done. They never take a thousand people and get them to leave prints all over different things, then lift them, and test to see how things work.
Missing the point, finger print are unique and impartial, it is the expert witnesses that are not. Finger print searching & comparison is made using points of comparison, certain features at certain locations. What's sometime flawed is the experts interpretation of that comparison, and the courts/jury blind acceptance of the expert.
and even further off-topic...
Reminds me of the old guy in The Shawshank Redemption. They let him out after many decades of "rehabilitation". He had been so isolated from society, so totally aloof, that he could not bear living in the foreign real world. So he hung himself.
Sometimes it just seems easier to jam our problems in a small dark hole and ignore them instead of actually trying hard to fix them.
It's 10 PM. Do you know if you're un-American?
they aren't tee hee, if you breath slowly, you can pass when you are lieing. And i think theres other ways as well,
No, No, No. Using your guesstimate, If there are 10^7 entries, then there is a one in 100,000 chance that a single one of them will be a false positive, not that one in 10,000 (sic) of the entries will be a false positive.
Completely aside from the factor of 10, you have used your 100,000 number in place of your 10^12 guesstimate. What you have argued is that if the error rate is 10^-12, then the error rate is 10^-5.
Have you spent any time in Florida lately?
Bingo Foo
---
taken! (by Davidleeroth) Thanks Bingo Foo!
It seams to me that if this were true the mere fact that we did not know until now, Means that fingerprints are unique enough to Serve as a form of self-identifacation.
So what if there not unique enough for a primary key ? I know I don't care.
You were born to die. Eat red meat and drink coffie!
It was interesting to read in the article that judges have recently had to come up with a better definition of science than "generally accepted" (which would make virgin birth science I guess). One of the requirements they cited was 'falsifiability'. I find this interesting for this reason: falsifiability is crucial for developing science but surely it is redundant in court. Suppose someone wanted to use X in court to prove A is true rather than B. If A is different from B and their argument is sound then this argument itself forms part of a test of the falsifiability of X. If, on the other hand X isn't falsifiable then there is no difference between A and B and so there is no reason why anyone would want to bring X as evidence. So it seems to me that 'falsifiability' is not a useful criterion for deciding whether a 'science' should be used in court (though I'm also saying it's not 'wrong' either). What does anyone else think?
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-- SIGFPE