Is the death penalty humanitarian?

If he cannot do anything useful then let people decide for the greater good.
if death penalty is the only solution then lets go for it.

I don't really see where the uncertainty principle comes to your equation, I assume it's common knowledge that many innocent people has been put to death in USA, that's why a govenor in Texas would parden 100 "death rows", which was heavily critisized by many.

Too many of the crime labs has been proven sloppy in their research, in producing accurate results, some would even produce false evidence just for the sake of profit.

If he stands accused for rapist, serial killing ..etc, I don't think it would be good to let his fate be judged by easily biased people.

Uhmm, didn't you read what I wrote in my former post? This is meaning innocent people has been put to death! And I'm talking about innocent psycotic people.

What i mean here is that instead of wasting another life, let just make it useful, in which he pay his losses by dedicating his life for productivity in which he does not benefit but the others, for the greater well being of all

two wrongs makes another one wrong, losing another life is not the payment for losing life, payment in which no one gains benefit, but only another loss.