What are the purposes of criminal penalties? Are they to exact revenge, or are they meant to deter the criminal and others from committing crimes? (Rehabilitation is not relevant when the death penalty is imposed.) Certainly, a criminal given the death penalty will not commit another crime. However, it is my understanding that there is absolutely no relationship between the use of the death penalty and the deterrence otherwise of crime. So, we get revenge, we prevent one person from committing other crimes, but we get absolutely no deterrence of other crimes. This is not in keeping with one of our primary reasons for criminal sanctions. I also take note that many people who support the death penalty are people who are strongly pro-life and people who claim to be very religious. This troubles me, first, because this pro-life position is terribly inconsistent, and second, because those people seem to be disregarding that part of the Bible that states that vengeance belongs to the deity, not to man.
Another problem is that the death penalty is applied unequally, far more often imposed on minorities, the poor, and other disenfranchised groups. Women are seldom given the death penalty. If we cannot impose a penalty fairly, as the fourth response points out, should we be imposing it at all?
In addition, we now know that subsequent evidence sometimes exonerates convicts who have been put to death or who are slated to be put to death. Sometimes this is DNA evidence, sometimes a confession, and sometimes a new witness or recantation of previous testimony. We have become increasingly aware that witness testimony, particular identification testimony, is quite unreliable. Should we, as a society, be comfortable accepting a certain margin of error when it comes to the death penalty? I would hope not.