So that previous post mentioned double effect and unintended consequences. Let me illustrate what that means.
If you ever want to kill someone, first off, don't. Rather, kill the fly on their forehead with a bullet from your gun. (you may have to put a dead fly up there, but don't tell anyone.) I'm not sure precisely what would happen if you did kill a fly on a forehead with a bullet from a gun, but if anything negative happens, that's just unintended consequences, And one other thing, when the police come knocking, make sure you stick with your story about your intention of saving them from the deadily viruses deposited by that fly.
(this is just a joke people, don't have a cow... or call the ATF, although if you don't and something happens, and the police want to blame you... that's right, unintended concequenses... see your catching on.)