Phage

Unfortunately there is the rub. Some people argue that killing is inherently wrong in all cases while others take the position that "murder" is wrong. Those arguing that killing is wrong in all cases usually do so using religion as a justification, and may as you said be using it as an escape from responsibility.

The thread title might be misleading because it asks if the death penalty is "Right or Wrong". Defining morality in my view requires using religion, and I think it is obvious that even if a majority hold a religious view we should not implement it as law unless it also fills a valid social need independent of religion. However, the first post also is "looking for some really good, concrete reasoning for either side," which the pro-death penalty side has provided in deterrent, punishment, simple removal of a problem, and revenge. I have not seen any religion-independent well-reasoned arguments against the death penalty yet, so I am starting to think that there is not one.