I have qualms about killing anyone for any reason. Not to say I'm incapable (not going into detail), but it has never sat well with me. Instead, I usually keep a solid six hours of gasoline in my car, and friends in just about every direction for that distance--if for some reason I can't get to a police station, I drive. And drive.
My current vehicle doesn't hold six hours worth of gasoline. OTOH, regardless of what vehicle I'm in, I've never had a problem finding either a place mine can go that theirs can't, or a road that they can't handle at a speed that I can.
Once they're out of sight or in the ditch, I go on my merry way.