Countertop is rightly happy at the thought of another rabid dog put down, unable to bite society again. Zendo Deb is equally rightly worried about the possibility of government incompetence smoking the wrong guy.
I still maintain that the death penalty is appropriate for attempted rape, attempted homicide, or attempted assault, when meted out on the spot by the intended victim.
I'm often asked why I have this atavistic tendency. Is it a love of vengeance? Do I somehow think that killing the bad guy will return his victims to life? No, it actually stems from something more pragmatic than that: When someone has violated the basic rules of the monkey cage so flagrantly, there's only one surefire way to make certain that they won't do it again.