As everyone knows from the movies, "tailing" someone who is driving a car never works. The driver turns around or looks into the rear-view mirror and sees the car following behind him or her, thus exposing the existence of the surveillance operation; the driver then takes "evasive action" or speeds up, and eventually manages to "lose" the "tail."
And so, police departments and other law enforcement authorities have taken to secretly attaching tracking devices ("beepers") to the automobiles or other pieces of personal property owned by people suspected of committing or planning to commit serious crimes. Small and relatively hard to spot, these beepers send out steady radio signals, which can be received and tracked by officers who are following behind, at a "safe" (undetectable) distance. Unless these beepers are in touch with ground-based relay transmitters or a GPS satellite, this distance can't become too safe.
Generally speaking, warrants are not required to attach beepers to cars that are parked in public places or places accessible to the public. But warrants are required to attach beepers to cars that are parked in private places, and to follow tagged cars if they leave public thoroughfares and start traveling on privately owned roads.
By e-mail SCP@notbored.org
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