The argument also falls apart if you consider that ALL justice is fallible. It is not much less of a tragedy to convict someone in error and take away 30 years of their life. Or 20. Or 10. So if we’re going to refuse to apply the ultimate sentence because we may err, how can we rightfully apply any sentence at all?
We administer justice not convinced of our own infallibility but with a faith that Due Process works. In the case of the death penalty, that Due Process is as rigorous as any Man can devise. And it works.
Justice must ultimately prevail, I agree.
But should also be seeking to improve the due process to ensure that when it is rendered, it is the most reasonable judgement rendered.
There is also the difference between cosmic and human justice.
I would assume the vast majority of those who wind up on death row have been career criminals for most of their lives. If one of them is executed for a crime he didn’t commit, that is a failure of human justice. It is entirely congruent with cosmic justice, with a little irony added for spice.
There is also a difference between “not guilty” and “actually innocent.” It is probable that many if not most of the cases that have been overturned with new evidence the accused actually committed the crime, with the new evidence merely weakening the case to where a conviction is no longer possible. IOW, he’s “not guilty,” not “actually innocent.”