Apparently police have a nice little system they can use nowadays. They can just swipe your ID (DL, or other) and get all sorts of info on you. I don't know exactly what they can get, but I know for a fact that it includes criminal record, traffic violations, existing warrants and if you have complained about anything to the police, or about the police. I'm sure this is really nothing new to most of us.
So now it became standard procedure to swipe everybody's ID indiscriminatly, if there is even a remote chance of them being related to a crime: Victim, witness, potential perps.
But on top of that, any policeman can slap a warning message into the system. They apparently play practical jokes on each other, like saying that this guy is a sex offender or a dangerous criminal, so they get the third degree when they get pulled over. Its all fun and games to them, because they can pull their badge out and explain the situation easely.
I can understand that this can be a very powerfull tool in crime solving. Unfortunatly what I see is a system that lends itself too readely to abuses. I know a few cops, we get along very well. But because I know them so well, I know that too many of them could care less about using/abusing this system.