i disagree with the assertion that putting someone to death is an offense to human dignity. i think it is quite the opposite.
you seem to agree he deserves death, but do not think the state should do it. you would rather turn a blind eye and let someone else enact what he deserves.
the point here is that as a human being, he should be treated as one. he is not an animal: he knows what he did. and because of that fact, because he is a human being, he deserves to be punished for it is his right. it is immoral to not give him the death penalty because it lowers the value of life and limb of those whom he murdered and injured. it strains belief that anyone could call life imprisonment for murder the "moral" punishment. the very arguments against the death penalty -- those about supposed innocence -- claim that because loss of life is incomparable to loss of freedom it should be abolished because it could be someone who is innocent who is executed. but that very argument shows the very necessity for it: you can't throw someone in jail forever for murder and call it justice, you just agreed that the two things are woefully unequal