I am opposed to the death penalty for some of the reasons others have mentioned.
It is without question not applied equitably across racial and socioeconomic lines. I don't think capital punishment deters capital crimes. And if the goal of the death penalty is to protect society from violent offenders, then that goal can be accomplished by a life sentence without parole just as well. To me it seems that the death penalty is vengeance, not justice.
And I guess I have an inherent distrust of the 'system.' I don't think it's worth what I call the moral risk that even ONE innocent person be executed. There have been many stories - I should go look for articles - of people being freed from prison when new technology can be applied to old evidence, etc.
Some people think that disapproving of the death penalty means that you have more concern for criminals than victims, but I disagree there too. Capital punishment doesn't bring back the loved ones that people have lost - the criminal dies, sure, but the violence is perpetuated and creates more victims. Now the family and friends of the criminal have lost a loved one violently too. I would prefer my tax dollars be spent intervening in the formative years and deterring people from turning to lives of crime - solve the problems of poverty and drugs and treat the mentally ill and you've gone a long way toward eradicating violent crime.
And who are we, as a society, to ask doctors, wardens, and the scores of other people involved in executions to actually *do* that job?! That's reprehensible, IMO.
If I die as a victim of a crime, I don't want the perpetrator put to death (and I need to put in my will so my wishes will at least be considered if there is a conviction).