Justice is not a penalty and best administered by the intended victim at the time of attack whenever possible.
Locking someone in a cell for the rest for the rest of their lives, 50 years or more, is not humane. And it has been well established there is no such thing as life in prison. Manson follower, Van houten, who was sentenced to death but commuted to “life in prison” after the California Supreme Court threw out the death penalty, was just granted parole by the parole board. She is only 66, still young by today’s standards. And if they don’t want to just wait it out, they can pitch their cause to one of the the “human rights” groups to start fighting for their release claiming any number of bleeding heart issues.