While I think the burden of proof needs to be very high, and the system that gets us there must be beyond reproach, I still believe in the death penalty. And I wish I didn't have to point out examples like this one to explain why I think so.
There should be a limit to how much damage one person can do during their lifetime. Once that limit is exceeded, there is no reason to allow them any more trips around the sun. And I'm not sorry for thinking so.