Well, I direct you to...the Spectre. And frankly, others. The Hawks for example; I can't imagine hitting someone in the face with a metal mace doesn't kill. They also had both Black Adam and Atom Smasher, who killed. I think the JSA has more of a guideline going than a hard and fast rule about no killing....for some of it's members. Okay, and Johns had PG kill the Joker once...very out of character. But yes, The Shadow can get rather murdery.