The punishment adopted by contemporary societies, life imprisonment, is inadequate in a hypothetical immortal society. Murder someone, go to prison for thirty years, and then go on to live for thousands more when you get out. It seems terribly wrong, devaluing life and making prison a reasonable bet. What's thirty out of a thousand, if you really hated the person?
You could bring back the death penalty in a big way (it's not heavily applied anywhere), although this would be somewhat at odds with immortalism. Plus the standard problems of sufficient evidence and legal expenses.
Perhaps we could ensure that life means life. But if this is an immortal life, the prisons will gradually fill up and up. A twist on this would be withholding life-extension from murderers, keeping them in a cell whilst allowing their bodies to degrade until cancer gets them. This seems rather cruel and unusual, particularly if a person had been genetically engineered to be immortal - you'd have to artificially induce aging.
Thoughts?
What's the purpose ? Justice OR vengeance and self-gratification in retaliating against someone who wronged you OR repair and if possible prevention of criminality ?
Death is not something I'd wish upon anyone. Not even someone I genuinely hated.
Death is ... nothing, a total waste. If you really wanted to make the guy suffer, so as to take your own petty revenge, then go for torture or something, at least you'll feel relieved (or at least hope you will) that you had the possibility to make him suffer. Make sure the guy knows why he's suffering, that he knows it's because he did something wrong.
Killing the same person just means that this person won't exist anymore. It won't suffer from being dead. The only way killing someone can be useful is by removing that person from the game, thus preventing further crime and damages to third parties from it. Or maybe you could make it clear to it that it is going to die because of its crimes, but that amounts to torture anyway. The question there would be, are you ok that the recipient of your torture disappears into oblivion ? Once it's dead, once again, it won't care anymore. See for yourself if any of those solutions quenches that very human thirst for vengeance.
If the goal is to correct a wrong, or prevent it, then again maybe death or very long detention could act as a deterrent. But that'd be hoping that people can learn from such punishments, which is not always the case.
We need more refined, efficient ways of preventing crime. I can't really think of any which would be free of side effects however. For instance, ubiquist surveillance systems could maybe help, but they'd mean the death of privacy, and possibly of freedom. Reprogramming criminals sounds like a good idea, but depending on how much you'd have to reprogram someone, you may as well say you'd be creating an essentially new person, therefore destroying, killing the former one. And who gets to decide who needs to be reprogrammed, when, under which conditions, to which extent, how ? Who gets to hold the power to craft people's minds into what they believe is fit ? What if that power is misused ?
As for correcting wrongs, nothing you can do to the criminal will directly restore what's been lost; albeit you might decide to use the criminal as a sort of slave, forced labor, and use that labor to repair, insofar as possible, the prejudice of its wrong doing, which would indirectly help restore part of what's been materially lost due to its criminal activities. That way of doing things may have less meaning in a post scarcity society though, since the ressource, work output of one individual would be negligible in face of the ressources and work availabe in such a society.
Once you've cared about the need for revenge, and the prevention, or repair of criminal activity and its consequences, I don't see what's left to care for; and in any case death doesn't seem like a fruitful approach, at best it can weed out criminals or deter them, at worst it's a waste of lifes, time, and ressources.
