I want to add my tuppence worth as well. Even if one day we have a justice system that can be 100.000% certain of guilt AND 100% certain that there is no chance of rehabilitation, I think we should still not have the death penalty, because I don’t think spending the energy and time killing individuals in cold blood is a healthy way for a society to behave. This Rudakubana guy may be some kind of monster, but that doesn’t mean that acting monstrously towards him is somehow acceptable.