My trashy neighbor's kid is terrorizing my family. Help!?

Yikes. If the kid's parents won't do anything about it then I don't see that you have any options other than to start the legal machine rolling. Surely as a cop your Dad must have some ideas on what can be done, such as restraining orders or something along those lines - I'm just guessing here. Bringing the law into the matter will only escalate it into full-blown community warfare, but I don't see any other course of action apart from getting a few people together, dragging this kid into an alley and teaching him a lesson the old-fashioned way...but, of course, that would be wrong. >:-)