Don't rely on the DA to do your job
I recently came across a story because it involved DNA evidence. Evidence had been tested 10 years ago, and the defendant - Stephen Meyers - was identified last year as a match. As is typical, odds were provided - a 1 in 1.6 million billion chance that the evidence did not come from the defendant. In preparing for trial, the evidence was retested - and guess what. That one in 1.6 million chance came true - the new tests excluded the defendant! As a result, the case was dismissed.
The case has a lot to teach us. One is that the estimates provided are just that; they are nothing but guesses, which have no place in a courtroom. The other lesson is that you cannot simply rely on older tests - even those that are incriminating. This was not a case where there were errors in testing. Instead, it was nothing more than new and more comprehensive test. Older tests were only able to look at several locations on the DNA molecule; results were given for each location. For example a person might be a type 1.1, 1.4 at location on 1.3, 1.5 at location two. If the defendant has the same types he is excluded. Newer tests look at more locations, which makes it more precise. If the defendant is excluded at any point, then he is excluded - i.e. cleared. Obviously, the more locations you look at, the better the chance of obtaining an exclusion.
What bothers me about this case is how the new testing came about - it was initiated by the DA. The defense lawyer apparently made no effort to re-test the evidence prior to trial. Instead, it appears they were prepared to attack the old evidence. Had it not been for the prosecutor, there is a good chance the defendant would have been convicted, and in prison as I'm writing this.
In my experience, prosecutors never challenge scientific evidence. If they have a 10 year old t est, they are going to run with it. If it's going to be challenged, it is up to the defense lawyer to do it. Kudos to the prosecutor here, who wasn't willing to blindly accept what the experts told him (even if they were just trying to make the case stronger)
I realize that this is not always a cut and dried issue. If the client is guilty, a retest will only provide stronger evidence of guilt. How do you know when to retest? In the end, you have to rely on the client, and your own beliefs. If you believe they are guilty, you must make them aware of the risks. If they are consistently maintaining innocence though, there is no excuse to not do everything possible to prove that, which would involve retesting.
Before the retest there was already plenty of evidence to suggest Meyers was innocent. The description of the suspect was short, fat and balding, while Meyers was tall and skinny. Not to mention almost no evidence to establish he was even in the same town where the assault occurred. You might thing that is enough, but I have seen far too many cases where defendants were convicted even though they didn't even remotely resemble the description provided. The explanations are usually that the victim was under stress, and that appearances change. In other words, if you are relying on a bad identification you are flirting with disaster.
Lawyers must be advocates, which means challenging all the evidence. Scientific evidence has received a free ride too long. It is up to us to challenge it. Mistakes are made, and evidence is never as conclusive as the scientists tend to believe. Don't get in the situation where you could have proved your client's innocence, and didn't do so.
