Unless I’m wrong, um, doesn’t the phone need the towers to actually make a phone call? To equate this to your location being unsecure is probably technically correct if they wanted to triangulate things? Am I on the right track here?
If you’re the sort of person doing things that has the authorities wanting a phone carrier to track you like this, then, err, what are you up to (don’t answer that)? If your activities are so nefarious then you should look at a different solution like an x-cellular phone (if these actually do what they claim anyway).