I thought this category might be dying, but I guess not. I found Snooping By Satellite by Declan McCullagh:
When Robert Moran drove back to his law offices in Rome, N.Y., after a plane trip to Arizona in July 2003, he had no idea that a silent stowaway was aboard his vehicle: a secret GPS bug implanted without a court order by state police.
Police suspected the lawyer of ties to a local Hells Angels Motorcycle Club that was selling methamphetamine, and they feared undercover officers would not be able to infiltrate the notoriously tight-knit group, which has hazing rituals that involve criminal activities. So investigators stuck a GPS, or Global Positioning System, bug on Moran's car, watched his movements, and arrested him on drug charges a month later.
A federal judge in New York ruled last week that police did not need court authorization when tracking Moran from afar. "Law enforcement personnel could have conducted a visual surveillance of the vehicle as it traveled on the public highways," U.S. District Judge David Hurd wrote. "Moran had no expectation of privacy in the whereabouts of his vehicle on a public roadway."
