Police Secretly Planting GPS Devices On Cars
An individual can reasonably expect to move about the world without having their movements tracked. Or, better, a person should retain the choice to keep their movements to themselves.
My cell phone can be used as a tracking device, but I can turn it off. My EZPass can report what toll booths I pass through, but I can remove it and pay cash, if I choose. I can wait for my neighbor to leave his house if I don't want him to see me leaving. And I can wait for my wife to take off with the kids before I visit my mistress.
Where I go and when I go there is my own personal business, and if the authorities want carte blanche access to it, they can get a warrant.