I'm guessing it's federal. Same rules apply on the west coast too. I came on the job in 1988 and I seem to remember it being kind of a big deal around 1989 that we could suddenly run any plate we wanted to 'cause it's not an invasion of privacy to run someone's license plate, especially while they are on a public road.
The same thing goes out here for tape recording people. We can tape record people without having to tell them when they are talking to us or when they are in a patrol car. There is no reasonable expectation of privacy while dealing with the police who are public officials. ( I believe you guys in Mass have different rules about that though. Too bad you can't get that rule changed!) We use tape recorders a lot out here. You'd be surprised what two suspects say in the back seat of a patrol car when they think the cops aren't listening!)
The same thing goes out here for tape recording people. We can tape record people without having to tell them when they are talking to us or when they are in a patrol car. There is no reasonable expectation of privacy while dealing with the police who are public officials. ( I believe you guys in Mass have different rules about that though. Too bad you can't get that rule changed!) We use tape recorders a lot out here. You'd be surprised what two suspects say in the back seat of a patrol car when they think the cops aren't listening!)