Our criminal justice system is fallible. We know it even though we don't like to admit it. It is fallible despite the best efforts of most within it to do justice. And this fallibility is at the end of the day the most compelling persuasive and winning argument against a death penalty.
Truthful words are not beautiful beautiful words are not truthful. Good words are not persuasive persuasive words are not good.
And I think there's something about conservatives frankly - and the Left when it comes to their channels of persuasion are unpersuasive. They are most of them are hate-filled obscenity-clogged rants of anger and hatred.
Unhappy let alone angry religious people provide more persuasive arguments for atheism and secularism than do all the arguments of atheists.