Catholic theologians' statement against capital punishment

Here (HT:  Grant Gallicho) is a letter, signed by a number of Catholic scholars and activists, called "A Catholic Call to Abolish the Death Penalty."  I agree with the letter's call.  That said, two quick thoughts:  First, my sense is that many death-penalty opponents are over-stating the matter when it comes to Troy Davis's factual guilt, and the "Georgia executed an innocent man" charge.  I do believe that our executive-clemency and other post-conviction review procedures are inadequate, but I am not sure it is warranted to charge massive and unfair breakdowns in this particular case.  The case, including the claimed new evidence, was carefully reviewed, several times.  (My own thinking is closer to Chuck Lane's, here.)  Of course, there is nothing remotely controversial or difficult about opposing the execution of innocent people; the challenge is to bear witness to the dignity of every human person by opposing the execution of people who are guilty of serious, awful crimes, as I still believe Troy Davis was (and as, for example, Timothy McVeigh was).

Second, I appreciate the fact that the theologians' letter calls specifically for legislative action to reform post-conviction procedures and abandon capital punishment.  As I've said elsewhere with respect to this issue, although I want our legislatures to end capital punishment, and have worked to bring about that end, I don't think the Supreme Court should presume to strike down capital punishment as unconstitutional.