Hmm.. It's hard to decide who's lives and who's not. I don't know if you are the right ones to decide that. But you can't leave a serial killer who killed kids to leave, even in jail. Any man who are in jail for a reason, there not actually punished, bcs they are still eat for free, have cigarettes for free even women to have fun. But even then I don't know if we have to accept the death penalty :/
Even the death penalty is very lenient now. Those who are sentenced to death usually go for multiple appeals, and this can take up to 25-30 years (appeals are made at the expense of the tax payer). Even after all this, the death row inmates may get a last minute respite and the death sentence may be commuted to life without parole.