I don't support the death penalty because it is not nearly humane at all.
It isn't humane for a criminal to harm or murder other people. Why should the criminal live after the people he has murdered have died? Execute him. But, be humane in the way he dies. Make it fast and for sure. Use the guillotine.

Why the offender who tortured his victim before death should be easily executed? It seems to me that the offender should know that he will incur an appropriate penalty. A quick death is too easy for such criminals.