The people who allow criminals with a record of killings to get another chance only to repeat the same infraction, are they same ones that would never take responsibility for the life they can potentially take in the future, and pretend it has nothing to do with them.
Many times killing is necessary, but they're too afraid of getting out of their moral high ground, or fence sitting to ever want to justify it, or care for any of the victims. Sometimes I feel criminals get more rights than a random innocent who gets murdered by them. Not that every single criminal should just get iced, it would depend on what they did. If you rob someone, and kill them or are an assassin, you shouldn't be given another chance, you took a life on purpose, you should expect the same to apply to you.