[link|http://z.iwethey.org/forums/render/content/show?contentid=293615|#293615].
The Supreme Court opinion in Furman v. Georgia addresses some of those issues. I think we have the death penalty because we (always?) had the death penalty - it was part of the American fabric like having firearms [link|http://www.deathpenaltyinfo.org/article.php?did=199|from the beginning].
Cheers,
Scott.