Assume that capital punishment is morally justifiable; lethal injection is not a good method. I ran across an article years ago that suggested another method: nitrogen asphyxiation. You can find the article easily online; just search for

"Killing with kindness - capital punishment by nitrogen asphyxiation"
National Review, Sept 11, 1995 by Stuart A. Creque

If what Creque has suggested is true, then nitrogen asphyxiation probably ought to be the only method used for capital punishment. Just use a small room with a couch and silently pump out the oxygen, replacing it with nitrogen. The condemned person would just fall asleep and die peacefully, without anything unusually fearful or painful.

Does anyone know about this? Is Creque right?