Affectively, one might ask, should murder be allowed?
The only difference between the state/country committing murder and an individual is motivation and methods.
The states motivations being punishment, revenge and, the claim at least, that the action deters the act in others.
The latter view apparently held despite the eleven thousand or so people murdered the U.S.A in 2014.
I mention the States as it is one of the few counties that still executes.
Is there a more inhumane act than to hold a person on death row for years and then finally decide to execute them?