The Troy Davis case is at or near the top of the news cycle at the moment, but I don’t know enough about the particulars of the case to opine on it (though there appear to be significant questions about his guilt). The case should, however, cause us to think about the death penalty.
I could write a long post about the pros and cons of the death penalty, capital punishment jurisprudence, etc. (having had Yale Kamisar for a Criminal Law instructor at the University of Michigan law school will do that to you) but I don’t find any of that necessary.
For me, the issue distills down to something quite simple: To be a proponent of capital punishment as it’s administered in the United States, I’d have to accept the fact that some number of people will be killed for a crime they didn’t commit. That’s the awful externality of the policy, and I think it’s too high a price to pay (and that notwithstanding the fact that there are some truly monstrous, obviously guilty people who I think deserve death). True, the logic of this principle extends to wrongful imprisonment generally, but the difference (obviously) is that capital punishment, once administered, affords no redress for the convicted. A wrongful imprisonment, on the other hand, can be redressed (with release and monetary damages), albeit imperfectly.
So, there you go.