The Truth about Evidence

The foundation of our justice system is that a jury of one's peers examines evidence to determine if one is guilty or innocent. But what happens when the evidence itself is questionable?

I was watching an episode of one of those television police stories and it mentioned a group of scientists in Israel who had discovered how to fabricate DNA and make a saliva or blood sample look like it was from someone other than who it was really from. So I went home and googled "fabricated DNA" and sure enough, a group of scientists in Israel have shown it is possible to fabricate DNA and make a saliva or blood sample look like it was from someone other than who it was really from. Of course, they also made a test that would determine if it was fabricated DNA or not.

It turns out that any undergraduate biology student can fabricate DNA and therefore, fabricate a crime scene. Increasingly, our society is turning to DNA evidence as the "nail in the coffin" when it comes to convincing a jury that someone is guilty. Or innocent, for that matter, because the Innocence Project, whose work I totally support, relies on DNA evidence to exonerate those convicted of horrible crimes they did not commit. And if it's easier to plant DNA at a crime scene than fingerprints, how reliable can DNA evidence in a complicated crime scene be? And what about those law enforcement agencies who are unaware that DNA evidence can be so easily fabricated and planted at a crime scene? How many truly innocent people are in jail because they were convicted by bogus DNA?

Another very common and trusted piece of evidence is eyewitness testimony. But I know from personal experience in my own life, when I recall a very traumatic incident in my life, in which there were several other witnesses, my story differs from theirs and they all agree with each other. So I am obviously mistaken in my "eyewitness recall", and yet in my heart of hearts I was absolutely certain it had happened the way I remember it. (Or course, ironically, something I remember from 14 months hold happened the way I remember it according to other witnesses that were there.) So how reliable is eyewitness testimony? Some studies have shown that up to 50% of people can have "memories" implanted by a third party or even by their own beliefs or assumptions. Many of the people exonerated by the Innocence Project were convicted based on "eyewitness testimony" because there was no DNA evidence linking them to the crime. Only the word of the victim who was so certain of their assailant.

In New York, a ruling in 2001 decreed that, on a case by case basis, judges must take into account the offer to provide expert testimony on eyewitness reliability if they believe such testimony will help the jury reach a verdict. But what this essentially says is that most people who serve on juries are unaware of how unreliable eyewitness testimony is. (Otherwise there would never be a need to have expert testimony on eyewitness reliability if everyone understood how unreliable they can be.) Which raises a bunch of new concerns. How well do juries know how easy it is for some people to lie without any of the usual "signs" of lying? How many people on juries know how DNA evidence can be fabricated? How many other "expert witnesses" are we going to need to explain to juries the finer points of evidence?

And finally, one of the most difficult types of evidence to understand is that from arson. The reason is that fire does not always behave as we think it should. Cameron Todd Willingham was executed by the state of Texas for the murder of his daughters by arson. But shortly after he was murdered by the state, an arson expert practically exonerated him because of the quality and findings of a review of the arson "evidence".

Arson expert John Lentini is one of the first to state that arson "evidence" needs to be thoroughly examined. Twenty years ago, Lentini was convinced that a man in Florida had murdered his pregnant wife and four children by arson because "expert" beliefs at that time suggested that the fire would have taken 15-20 minutes to reach "flashover" (the point where the fire is so hot, everything in the room just bursts into flames simultaneously). In fact, when the arson investigators had a chance to re-enact the fatal fire in a home that had the same layout and the same furniture as the other, the room reached flashover in about 4 minutes! Fortunately, Mr. Lentini testified to the truth of the evidence and an innocent man was not sent to death row.

In Mr. Willingham's case, it's too late. (Just one reason I don't support the death penalty!) The burn patterns that fire "experts" originally thought indicated intentionally set fires turned out to be something completely innocent. And like Mr. Lentini, when the fire was "recreated", it burned exactly like Mr. Willingham said it had. But now he's dead and the state of Texas can't bring him back. But the state of Indiana may soon grant a new trial to a woman it convicted in 1996 of arson and murder for the death of her three-year-old son, an "arson" experts now say would have been impossible. While the woman may eventually be free, nothing will bring back the 14 years she's already lost of her other son's life.

So how is one to judge evidence? That's not a question I can answer, but I can say that if I am ever picked to serve on a jury, I will remember the truth about evidence.