It's plausible to assume that they can already track your car if you already have a GPS system installed anyway.
If they have probable cause I don't really see an issue with them tracking the comings and goings of my car. Bear in mind that I generally tend to agree with police having the right to do pretty much anything short of infringing on human rights. Privacy is trivial when justice is obstructed. Either way assuming that we currently have any true privacy is somewhat naive.
My hypocrisy is that I'm anti-government, for the most part. Yet when it comes to crime I respect the police, or more accurately I respect the idea of the police. That said, I've always lived in countries where the police are a dominant authority: you do not F with the police; you even speak with a disrespectful tone and you could get in trouble. Granted I have had moments where I was disappointed, like when we got robbed last year and the cops just seemed so nonchalant about it "Yeah, we'll see what we can do.. Don't hold your breath." There's not much to be said or done about it.
Naturally, the problem in giving power to the police (or any authority for that matter) arises when there is corruption. It's a damn shame when it happens.
