Two Oklahoma inmates on death row are actually petitioning the courts to put them to death with a firing squad instead of the complex 3 injection system of poison that is currently used.
If you think about it, it is probably less cruel. A bullet to the head is pretty much painless (so I’m told) since you are dead before you realize it.
Plus it is way cheaper, even at current ammunition rates. I’m sold, shoot the bastards!
Problems? First, somebody will have to clean up the mess. Second, not sure if it is still a thing, but usually there are two switches, one on a dummy, so that the people who throw the switch do not know for sure they have killed someone. A bit tougher with a firing squad.