I oppose the death penalty, but not because I think it’s wrong to kill some criminals. I am perfectly fine with ending people like Tim McVeigh or Susan Smith. My problem is that I don’t have confidence courts can reliably tell who deserves and who doesn’t.
They always say the death penalty is for the “worst of the worst”, but many arbitrary factors can make the difference. The race /social class of the criminal/ victim. The ambition of the prosecutor. The location of the crime.