Hear me out: I propose a death penalty for specific crimes. If evidence is damning for murder/man slaughter, then the ones found guilty should face death, not just lethal injection shit either. Since they bought hell to their victim they should face a death that’s voted on by a court or picked randomly. Say, dropped into a volcano, but first, locked in a cage /box. Or, dip the guilty into cement (alive of course) and bury them. No one would miss them, say if the suspects were cold sick killers like the one in the story, or if it was a family duo and killed children.
Our US prison system is already dysfunctional but we give cold killers a place to sleep, converse, exist even. Rehabilitation can work for some, but not all. Even if in this case it was some foid or whatever, the man is still going to see the light of day, for some time.
(EDIT): Noted he is in the UK but it still goes. The man will spend time in a cell instead of Davy Jones’s locker (underwater stuffed in a literal gym locker)