To my mind, tracking a vehicle/person's movements sounds pretty much like a search. What concerns me is that they didn't have any reason to conduct that search

To my mind, tracking a vehicle/person's movements sounds pretty much like a search. What concerns me is that they didn't have any reason to conduct that search in the first place. It surprises me that the cops don't need a warrant to track anyone for any reason - that's very much open to abuse as cops are not known for being impartial.