Non-venomous snakes should not be killed. Venomous snakes should only be killed if their presence endangers humans or pets. More than 80% of snakebites occur when a person is trying to kill or handle a snake. This is because North American venomous species will not actively pursue you, and they can only strike up to 2/3rds their body length. By killing it or trying to handle it, you are putting yourself in that strike zone. If the snake is encountered outdoors, the best defense is to back slowly away from it.