I came across this article by Mark D. Rasch, J.D., a former head of the Justice Department's computer crime unit, who now serves as a lawyer specializing in computer crime, computer security, and privacy matters. He explains how it is easy for the US government to subpoena a person's location history from their cell phone company:
http://www.securityfocus.com/columnists/376
…I had long wished that somebody from the legal community would weigh in on this– thanks Mark!
