Quoting
Zack Snyder
I perceive it as him not killing directly, but if the bad guy’s are associated with a thing that happens to blow up, he would say that that’s not really my problem. A little more like manslaughter than murder, although I would say that in the Frank Miller comic book that I reference, he kills all the time. There’s a scene from the graphic novel where he busts through a wall, takes the guy’s machine gun…I took that little vignette from a scene in The Dark Knight Returns, and at the end of that, he shoots the guy right between the eyes with the machine gun.