I don't have a problem as much with the police doing this, but I have a huge problem with them being able to do without a search warrant . What if they saw me bringing pots of plants into my basement from a distance and decided I was growing marijuana (without any further investigation) and then put a GPS on my car. That's wrong, imo, but the judge is saying "oh that's totally cool. don't even have to ask us, go ahead and sneak onto her lawn and hook her car up to your tracker."