Earlier this week I blogged about the retesting of DNA evidence in the murder of Wanda McCoy. Roger Keith Coleman was executed for the crime 13 years ago, but various people have been insisting he was innocent and asking for the evidence to be re-tested.
Now it has, and the results were about what I predicted: The DNA matched with 19-million-to-one odds against an accidental match. Fresh DNA matches are routinely in the billions-to-one range, but for a degraded sample, that’s pretty definitive.
Some have objected to these tests because they weren’t about finding the truth but were all about politics and abolishing the death penalty. For those most closely involved, I imagine that’s true. Nevertheless, a lot of truth was found.
Supporters of Coleman’s innocence are devestated. Long-time supporter James McCloskey described it as “a kick in the stomach” and feels betrayed. At least now he knows better than to spend more time on Coleman’s behalf.
Prosecutor Tom Scott, on the other hand, feels “like the weight of the world has been lifted off of my shoulders.” That’s got to feel good. If the tests had gone the other way, he would have been blamed for the death of an innocent man.
I believe the search for the truth is generally a good thing, even if those doing the searching (or those trying to stop them) have less-than-perfect motives.
This is how scientific thinking works. We have this theory—that special relativity is true, that other stars have planets, that Coleman is guilty. Then we test this theory—with particle accelerators, or telescopes, or DNA tests.
If we find what the theory predicts—extended particle life, Doppler shifts, a DNA match—then we can all be a little more confident that the theory is correct.
The DNA tests also tested the more general theory that the process of capital punishment is accurate. That theory also passed its test so we can be a little more confident there as well.
Thus we gain knowledge.