When you include the cost of appeals etc we spend more than that (on average) actually killing someone. In the old days of trial > hanging your argument was more reasonable, but we also killed more innocent people back then.
That's just an argument against our current court system. We allow virtually unending appeals, even with no new evidence or reason for believing that the earlier trials/appeals were somehow unfair. Some states have (or had) mandatory appeals for capital cases, even when the defendant plead guilty and didn't contest the death penalty.
