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."

Comments

well, well...

[fyngyrz]

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.

Re:well, well...

[D'Sphitz]

I agree 100%. We see all the time stories about new evidence in death row cases. The first thing the prosecutor always argues is "he doesn't deserve a new trial, I stand by the conviction". If they truly cared about justice they'd say "hey we need to take another look at this". I don't know how they can live with that on their conscience anymore than I understand how defense lawyers can live with setting rapists and killers free on technicalities. I think the answer is that most lawyers in general lack a conscience, you'd have to to be successful.

I have seen first hand how the justice system truly works. Back in my youth I was a bit of a delinquent, and was convicted of many fairly petty crimes, mostly misdemeanor but nothing worse than a gross misdemeanor. I freely admit that I was usually guilty as charged, and I took my licks, but there were two cases where I was absolutely innocent.

Part of their strategy is to charge you with everything in the book, that way when plea bargaining comes around they can act like they are doing you a favor by dropping the extraneous charges if you plead to the main charge. The prosecutor had absolutely no interest in justice and wasn't interested in explanations or evidence, it was made very clear that if I refused to plead guilty it was going to cost me. In retrospect i'm confident I would have won both cases had I gone to trial, but the scare tactics can be quite effective, especially on a 20 year old kid.

I accepted the plea bargain in both cases to stay out of jail and avoid a costly trial and missing more work. Being innocent is just as costly as being guilty. Ironically I had to tell the judge under oath that I was really guilty and wasn't just saying so for the sake of the plea bargain. The convictions went on my permanent record and I got some hefty fines and probation, and the prosecutor got 2 more notches on her holster. 8 years later these convictions in particular, which were gross misdemeanors, cost me a very nice job.

Like I said, it was fairly petty and doesn't compare with the innocent people who are rotting in prison right now, but I can definitely sympathize. We see it all the time, people pleading guilty to avoid the death penalty or long prison sentences. When it is more of a punishment to prove your innocence than it is to plead guilty, something is wrong with the system.

Re:well, well...

[Archtech]

Yes, but regular fingerprints are actually very good. That's why it's called "DNA fingerprints" and not "DNA shoeprints" or "DNA ballistics evidence".

Brandon Mayfield might disagree. Had he not been able to prove beyond a shadow of doubt (as in hundreds of eyewitnesses) that he was in Portland, Oregon when the FBI said he was killing people in Spain, he would have been in a peck of trouble.

Note the closing sentence of the following story: "an FBI fingerprint examiner told an expert hired by Mayfield the original print no longer exists".

Fancy that.

http://www.policeone.com/investigations/articles/88280-Newspaper-Faults-FBI-Examiner-in-Madrid-Bombing-Fingerprint-Case/

Note that it doesn't really matter whether the actual fingerprints were a perfect match or not. What matters is that the FBI lab said they were.

Transparent government

[Anonymous Coward]

Please support radical transparency and open source the government.

If everything is out in the open, there can be no hiding.

very worrysome

[Anonymous Coward]

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?

We're seeing no such thing.

[raehl]

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?

Practical truths...

[fahrbot-bot]

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.