McGrath - I don't think I implied that I think people are incapable of change. One of the great things about people is that they're always capable of change.
Which is an argument that I didn't include in my previous post, but due to lack of time can't really adress now. Basically: Murderers are mot always intrinsically evil people. Those who kill in the heat of the moment tend to feel remorse afterward. In that case, applying the death penalty is just revenge rather than a punishment.

In the case that was linked to above, of the serial killer, I don't think he could change. Therefore he should be kept away from society, but I still don't think that justifies killing him.