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FBI Fights Testing For False DNA Matches
Statesman writes "The Los Angeles Times reports that an Arizona crime lab technician found two felons with remarkably similar genetic profiles, so similar that they would ordinarily be accepted in court as a match, but one felon was black and the other white. The FBI estimated the odds of unrelated people sharing those genetic markers to be as remote as 1 in 113 billion. Dozens of similar matches have been found, and these findings raise questions about the accuracy of the FBI's DNA statistics. Scientists and legal experts want to test the accuracy of official statistics using the nearly 6 million profiles in CODIS, the national system that includes most state and local databases. The FBI has tried to block distribution of the Arizona results and is blocking people from performing similar searches using CODIS. A legal fight is brewing over whether the nation's genetic databases ought to be opened to wider scrutiny. At stake is the credibility of the odds often cited in DNA cases, which can suggest an all but certain link between a suspect and a crime scene."
What we're seeing here is a crack in the government's facade of fake-goodness. The ideas we're fed are that justice is blind, which means (we're taught), ultimately fair; that prosecutors and judges and the legal system in general have our best interests at heart, and so on, platitude after platitude...
But the truth peers 'round the corner here. They're not interested in accuracy, else they'd be all for determining how well this works, or not. The process and the results would both be open. What they're interested in are convictions, because that's how they keep score. That's how the public is keeping score.
This is unfair and irresponsible on two fronts. First, if you get the wrong person for any reason (including using DNA evidence that is supposed to be basically infallible, but is, in fact, fallible); then you've done a wrong to that person, of course. But secondly, for every false conviction the prosecutor and their accomplices notch into their pistols, the real criminal is now completely free -- the case is closed. They're not even looking.
As a society, we need to stop trying to raise up any part of the system based upon count of arrests, convictions, tickets, etc. The temptation to go for easy answers is too high; obviously, if the FBI itself is victim to this, an organization that prides itself on its organizational integrity, groups that have less tradition of trying to do right -- like the local cops who broke down your neighbors door last week -- are going to fall even more prey to such pressures.
As we see that the FBI tries to prevent the truth from coming out about a tool that is less effective than they claim, as they try to prevent exonerating information from reaching the defense, we see true colors.
These people are not our defenders; they claim to be, but they have their own agenda, and it is not about fairness. They're simply counting scalps.
I've fallen off your lawn, and I can't get up.
Please support radical transparency and open source the government.
If everything is out in the open, there can be no hiding.
This story is total scientifically illiterate bullshit. A 9-locus match between unrelated people is not surprising. That's why we don't sue only 9 loci, idiots! There has never yet been a 13-locus match seen between unrelated people in the national database- despite the 5 million or so profiles currently in it. I'm sure the average Slashdot reader can manage to work out how many pairwise comparisons that is. (Hint- it's a pretty fucking big number.)
No, it's not wrong. There are over 5 million profiles in the national database. Any slashdot reader should be able to work out how many pairwise comparisons are made when a database that size is searched against itself, and what the expected number of hits is when the match probability is about 1 in 100 billion.
This story is old news, and simply illustrates why we use 13 loci (average match probability around 1 in a quadrillion or less) and not 9. There has not been a 13-locus match between unrelated people in the database, confirming that the match probability estimates are indeed conservative as they're designed to be.
Why would they (law enforcement) not want there to be some doubt to DNA results? They're also being used to overturn old convictions. In the case of current investigations, there is also other information (fingerprints, etc.) to help match a suspect to a crime...
www.joking.net
As an American once arrested by the SS/FBI for computer related crime a while ago, DNA testing always worried me. I can understand it for violent offenders (which is how it was started and then carried over to all felons).
I can also tell you, if you refuse to submit to testing, they give you what they call "diesel therapy," taking you away from the cushy club fed camp you were in and busing you around the system until you relent. If you were given a half way house sentence or probation, they can revoke either for not submitting a sample.
Dispite turning my life around, finishing my degree and now working as a developer for a medium-size firm, I worry at times that one night I'll be hauled away because some flunky at the FBI mixed up DNA samples or didn't compare them correctly. I can imagine this being a horror scenario for anyone who's never broken the law, but can anyone imagine there being even a slight chance a bunch of narrow minded, non-technical cops are going to believe me, even if the crime is something totally unrelated to my history?
What we're seeing is a consequence of basic math.
1/113 billion chance a particular person has the same DNA profile as me. 6 million records. So I have a 6 million / 113 billion chance of matching someone else in the database. Drop some zeros and thats 6/113,000. Of course, each of the 6 million people in the database has a the same chance of matching someone - so that's 6/113,000*6,000,000 - which means there should be 318 people who match someone else in CODIS, or 159 'matches'.
# of people matching = size of group * size of group * chance of match
Anytime you have something that has a small chance of matching, but a fairly large sampling group, your chances of matching are high, because your chances of a match existing within the group is the SQUARE of the group size.
So it would be surprising if there were NOT people who matched in CODIS. The question is, are there more or less that 318 of them, and how much more or less?
paintball
I think the really cool thing about this whole story is what it says about "race". For hundreds, if not thousands of years, and even now, people have using "race" and skin colour as reasons for subjugation. But here we have the first cast of extremely close matching DNA, 1 in 113 billion, and they are from different "races". Wow.
This, if anything, should dispel any stupid theories about the difference of "race" within the human species.
"We have to refocus everyone on the Rights of the Innocent"
No, we need to focus on rights and fairness, period. Cops aren't always truthful. Drug dealers sometimes don't lie.
Renaming basic human rights and due process, i.e. Rights of the Innocent, to some special "needs" category plays into special interest. Much like how "victim rights" laws throw to the wind fair court cases; the defense has their name thrown in multitude of papers and intense scrutiny, while the victim hides in anonymity. This has resulted in inequities in handling of cases--this become hugely apparant in both the Duke rape case and the Kobe Bryant rape case; consider these were big name cases where the flaws were apparant and utilized by the prosecution. (If you're wondering what should happen--if the victim's name is protectd in a case, the defense's name should also be protected in the case.)
Furthermore, such new terminology often is at some point redefined and abused--most of the citizens of the United States still don't realize that "violent" offenses constitute mere drug use or sex (so called statutory rape) under the 1984 Bail Reform Act (this is why California's 3 strikes laws ends up taking in so many repeat offenders). I can easily see "rights of the innocent" laws being ineffective and creating a special class as one-time DUI offenders now accused of murder get denied a "special class" of rights.
The facts are rather simple--for the past 60 years, laws have gone overly pro-prosecution. Part of this is government keepign score, as someone else put it. Part of this is also on the general public for being stupid, scared, and greedy--why people will look less horrified at a murderer than a pet killer, or if they see someone shackled they presume guilt, or see some sick social advantage in another person being locked up (prison doors open as the economy tanks means more jobs for the "innocent" sort of thinking).
Not to troll, but law enforcement agencies are really more interested in convictions than the truth. For instance, Virginia has a law that places a 21-day time limit on new evidence that can be used to exonerate someone wrongly convicted. I'm sure the FBI doesn't want it's coveted CODIS database subject to any doubt.
It must have been something you assimilated. . . .
Very true. When's the last time you saw any kind of cop show, where they admitted to have screwed up? I can only remember it being done in Numb3ers in two episodes. One and a half actually, because only one of the shows talked about the fingerprints being misidentifed and the wrong guy being thrown in jail. The other was just a wrong assumption on their parts resulting in a manhunt.
Hell, I'd love for a show like 24 to have Jack Bauer or whomever torture the wrong guy for hours on end only to finally realise "woops - wrong guy. Guess the stuff he admitted to was just to get out of more beatings"
We do not live in the 21st century. We live in the 20 second century.
Unchecked state power is a danger to everyone. The FBI's court filings to prevent DNA statistical studies are transparently self serving. Imagine if they got their wish and had everyone in their database. Million of innocent people would be subjected to unreasonable suspicions. Such plans should be abandoned and all efforts made to release people who were wrongly convicted, something that DNA testing seems to be good for. Great injustice has been done because the state granted itself the power to punish based on what it considered reasonable extrapolation instead of truth backed up by real data. It reminds me of witch trials.
Prison violence proves that surrendering your rights to the state does not make you safe. All kinds of state wards have suffered all kinds of abuse in direct proportion to the control and trust guardians are given. It is nearly impossible to administer justice in a place where no one is trusted but abuse must always be checked for and discouraged. This is one of the reasons state supported torture is so horrible. A cruel state that is more interested in punishment and revenge than it is in justice and protection will abuse guilty and innocent people alike. The ultimate abuse, however, remains the loss of life.
one of the key witnesses for the OJ trial, I forget his name, had said that DNA was a great tool for excluding suspects BUT not good enough to ID them. He was a noble prize winner for his work inventing PCR dna tech. Of course everyone dismissed him at the time as a hired gun for OJ, I guess he gets the last laugh today!
The only way to bust a doper--is when you yourself become a smoker!