MEGAN MCARDLE: “I confess, I am opposed to the death penalty for other reasons, but I think that even if you think it’s morally acceptable to execute the guilty, the long string of exonerations suggest an error rate in the justice system incompatible with executions. Remember, most cases don’t even have DNA evidence, so we’re certainly not discovering all the innocent people we’ve sent to jail.”

As I’ve said before, I don’t think there’s anything inherently immoral about the death penalty, but Charles Black’s argument about the inevitability of caprice and mistake is looking better and better.