I live in Texas, so it would be legal (though perhaps not advisable) to shoot the dog for trespassing, it might be similar in your area. My uncle (a police officer) said (at least from a legal perspective) it would be better to shoot and ill a trespasser than say use rubber bullets which would harm without killing, presumably because we could be held liable for the injuries, but a dead person can’t press those charges, and we would be legally protected by trespassing laws.