I once did a jury trial where they had my guy’s DNA. I mean, I’ve had a lot more than one case where there’s DNA. A lot of them don’t go to trial though. That’s because DNA seems so definitive. It’s exact. They can exclude the rest of the world to say your guy did it.
In my case, it was the defendant’s theory that the defendant was never at the scene of the crime. The DNA, of course, was found on a beer can that was at the scene of the crime. At first blush, it looked like we were screwed, right?
Maybe. When the guy from the crime lab (or, the “DNA Dork” as I’m prone to calling them in casual conversation- ask a DNA expert about DNA sometime and you’ll see why) testified, I didn’t really contest any of his methods or calculations or even his linking the beer can from the crime scene to my client. In trying to explain DNA to the jury, though, he did a pretty good job of explaining it in a way a layperson would understand. The first thing he said was that “DNA tells a story.”
That’s what I crossed him on. The story. DNA, when perfectly collected and analyzed tells a story. It doesn’t tell a “Who Done It” story. It doesn’t tell a “this guy is guilty” story. It’s not that smart.
It tells a story of contact. A story of touching. A story of who touched or spit or bled where. And on what. It tells that story when it’s properly collected, stored and analyzed, anyway.
In my case, it told a story of my client touching a beer can at one point. It didn’t tell a story of where or when he touched the can. Or, more importantly, how the can managed to get to the crime scene. It didn’t tell any of that.
Coupled with the State having to use a witness that was an absolute buffoon and the police not doing a very good job, that allowed the jury to see the absolute innocence of my client. Or, at least feel comfortable signing the “Not Guilty” verdict form, anyway.
So, maybe DNA isn’t all it’s cracked up to be. Maybe, 30 years from now, the FBI will be reviewing all it’s DNA cases as potentially faulty just like it is reviewing all its old hair analysis cases. Maybe someday DNA will be looked at with the same suspicion as police canine searches– as something that could be accurate when used correctly but probably isn’t used as correctly as often as it should be.
I’m already looking at it like that now. So is the New York Times, which today ran an opinion piece called, “High-Tech, High-Risk Forensics”. They also realize that the story of how DNA gets wherever it ends up is more important than whether or not it’s there:
Once presented with Mr. Anderson’s [alibi] hospital records, prosecutors struggled to figure out how an innocent man’s DNA could have ended up on a murder victim.
Late last month, prosecutors announced what they believe to be the answer: the paramedics who transported Mr. Anderson to the hospital were the very same individuals who responded to the crime scene at the mansion a few hours later. Prosecutors now conclude that at some point, Mr. Anderson’s DNA must have been accidentally transferred to Mr. Kumra’s body — likely by way of the paramedics’ clothing or equipment.
This realization, of course, came after Mr. Anderson sat in jail facing life in prison for nearly 5 months. That case was just a fluke, though, right? No need to get all bent-out-of-shape about one guy spending a night or 200 in jail, right? Right:
In one famous case of crime scene contamination, German police searched for around 15 years for a serial killer they called the “Phantom of Heilbronn” — an unknown female linked by traces of DNA to six murders across Germany and Austria. In 2009, the police found their “suspect”: a worker at a factory that produced the cotton swabs police used in their investigations had been accidentally contaminating them with her own DNA.
As if that’s not scary enough, the article’s discussion of the accuracy of DNA to pinpoint a specific person is even more scary:
Contamination is not the only way DNA forensics can lead to injustice. Consider the frequent claim that it is highly unlikely, if not impossible, for two DNA profiles to match by coincidence. A 2005 audit of Arizona’s DNA database showed that, out of some 65,000 profiles, nearly 150 pairs matched at a level typically considered high enough to identify and prosecute suspects. Yet these profiles were clearly from different people.
I know that probably doesn’t bother you. It wigs me out, though. The fact that random DNA has the police running around and arresting people who shouldn’t be arrested, and the idea that DNA may not exclude “the entire rest of the population” (as the “experts” have been saying for decades) paints a fairly uncertain picture of the world we live in.
But, I’ve suspected that for years. So has just about anybody else on the criminal defense side of things. Now, the New York Times does as well. It will be interesting to see if things change any time soon. I doubt that they will.