Don't criminals still spend time in jail before execution?
Prison, not jail. Jail is where they hang out while they're still on trial. When they're sentenced, they get sent to prison.
Isn't the wait before death punishment in itself?
No. If it were, there wouldn't be a death penalty. That time in prison... that's borrowed time. They've been sentenced, but are kept from serving their sentence until a lengthy appeals process to make sure that the court didn't screw up.
I wish I could wait 20 years after being pulled over before having to pay a speeding ticket.
Not only do they owe the state their life by virtue of having been sentenced to death for a capital crime, they also owe the state whatever it spent keeping him alive before executing him. They oughta put death row inmates to work. Let them earn their last meal. And if they have to suffer for a few minutes before they die, so be it.
I think it must be very stressful and psychologically/emotionally harmful.
It must be. And it should be. They're murderers.