People who are familiar with my ideology would probably be shocked to find that I chose undecided.
When I hear about a case where someone was brutally murdered, my blood boils and I admittedly go into that "fry the b*****d" mood as clearly that person is no longer human and deserves what he/she gets. That's the emotional argument for the death penalty.
On the other hand, in less emotional moments, I wonder what gives the state the right to take someone's life. Granted the Constitution (for those of us in the US) allows the taking of life with due process, so it's not a question of legality. It's more of a moral argument similar to what Wendy, Labby, and Yvonne and others have argued for.
I do believe the death penalty does work to hold down violent crimes as do other methods like the right to carry concealed weapons. If the goal is to provide safety to the public, it seems that the threat of severe punishment could serve as a deterrent if done correctly. Just ask Singapore about their laws. While seemingly draconian to most of us, people rarely commit violent crimes because of the knowledge that the government is very serious about punishment.
In this country, it seems that the death penalty is handed out without any consistency. If the penalty for murder one is death for one person while another is 20 years to life, I just don't see how it could work as a very effective deterrent. I'm not necessarily advocating a transition to the Singapore laws, but there's no doubt it works there. Some sort of consistency has to be in place.
So in essence, I am for it sometimes and against it other times, both for reasons Pam has stated and for reasons Wendy, et al have mentioned.