If the person has a life sentence there’s a reasonable chance he or she earned the sentence for doing something horribly bad.
Why would you want to shorten a life sentence to 99 years? If the person is truly immortal, then 99 years is a drop in the bucket and in a 1000 years it will be forgotten entirely.
The way I see it, tough shit for the criminal if he turns out to be immortal. Don’t do the crime if you can’t do the time, even if the time means… forever….
I would hope that IF Charles Manson had been immortal that the parole board would have continued to deny him his freedom for millions of years to come!!!
Remember that the supposed person in question is immortal, not indestructible. Cut their heads off and stick it on a spike out in the Sahara, and tie their bodies up to a tree in the darkest jungle where the lions, tigers and bears live. Some fates are worse than death!
Yeah, even if they were indestructible, but not super-powerful, you could probably seal them up to their neck (or, encase them) in a block of cement, and or force them to watch bad TV forever, or something.