You’re asking the wrong question. Nobody who criticizes the death penalty say criminals want to die, they’re saying fear of the death penalty doesn’t stop crime. Of course with Loughner being nuts none of that discussion relates at all.
Of course NOTHING stops crime; AND the death penalty deters crime:
1) Proven fact: Every executed criminal NEVER kills again.
2) Why don’t these massacres occur in a gun store, gun range, police station, etc., except that the perps do not want to die; they want to kill?
3) Why would any of these perps ever surrender instead of charging the arresting police with their guns drawn, except that the perps do not want to die; they want to kill?
4) Why do the perps plea to a deal that takes the death penalty off the table, except that the perps do not want to die; they want to kill?
5) Why, after conviction, do they fight the death penalty, except that the perps do not want to die; they want to kill?
just saying...