" am for this in principle, but it costs so much to kill off one of these SOBs that I wonder if it might not be far cheaper to house them for life with little if any human rights."
I'm with you, actually. Not to mention that all the appeals in death cases clog up the courts, thus denying swift justice to perpatrators of other crimes.
Put the guy in prison for life and throw away to the key. He doesn't get to write books any more. No more visits or interviews. No more appeals to the courts.
Better to have him spend the next forty years wishing he could die than granting his wish right now.