You are correct: God did not create people to do that.
Under our system life is taken from people only after a judge has considered the case and so ordered that the person forfit their light to live.
While we might say that certain acts are worthy of death, few of us would really want death to come by murder. We say that when we sentence someone to prison, we than have an obligation to protect them from murder by another prisoner.
As I understand it, TS has not pled to a crime that carries the death sentence. Therefore, society has an obligation to protect him from murder by another prisoner.
On another point: My personal opinion is that long prison sentences are harsher punishment than death sentences.