“Is that a trick question?  You see my dog?  I love my dog, but if it had rabies, an incurable disease that makes dogs uncontrollable, I would have him put down.  Some humans are uncontrollable, for reasons we don’t comprehend.  I don’t mean the stoked-up kid who shoots a liquor-store clerk.  I mean creatures in human form who don’t have any souls, or whose souls have been eaten out of them by evil.  As Ted Bundy said, `What’s the big deal?  There are so many people.’

Almost always these guys admit to the crime, and there’s so much evidence that the situation that Butch was talking about, where an innocent guy is nailed because of framing or miscarriage or crummy defense, just doesn’t arise.  It’s not psychology or bad home life either that makes them do it, it’s evil.  I believe in the absolute physical reality of evil, which is good doctrine, by the way, Lucy. They can’t repent. Posse non peccare, as Dante says, they are incapable of not sinning, they’re already in hell, but don’t know it, and they’re simply too dangerous to stay on this earth.”

‘Maybe, but we can’t know that, Mom,’ said Lucy.
’You can’t substitute human for divine judgment.’

Marlene smiled, and it was such a bleak smile that Murrow, who had been studying her face, was abashed and turned away and felt the hairs rise on his neck.

“Therefore, kill them all,” said Marlene. “God will know his own. Who wants hot fudge?”

True Justice (Fiction), Robert K. Tanenbaum

Pretty much sums up my views on the Death Penalty.