I agree the death penalty is extreme for extreme cases. However imprisonment for long periods of time is cruel and unusual punishment that results in repeat offenders. So I say exile them to an island and let them either form a society or kill each other. What ever happens then is on their own heads.

I have no faith in human perfectability. I think that human exertion will have no appreciable effect upon humanity. Man is now only more active - not more happy - nor more wise, than he was 6000 years ago. Edgar Allan Poe