Don't presume that because you believe it would hurt you if you were in his shoes, that it must hurt him.
Death comes to all men in time. Contending against the state as if capital punishment is somehow more heinous than--say, a child's death by cancer--is silly and phony.
I note the rich and influential never get this ultimate punishment. But poor folks do, and their demographics are troubling to analyze.
I do not wish to see the state passing judgment on anyone's right to exist, be they an innocent in the womb, or a perpetrator of a horrible crime. I understand the feelings that cry for death to be doled out to murderers, but I respectfully remain unconvinced true justice is served by using a punishment that disrespects the murdered ones involved if the wrong people are executed, and doesn't bring anyone back to life who deserve to be live more then the one who caused them to die.
This is far from aan easy question to deal with. I have agonized over it for decades, and I expect I will ponder it as long as I live, of that I have no doubt.