WASHINGTON — The government is free to attach a GPS device to the car of any American and record that person’s public movements for a month or more without a warrant or suspicion of wrongdoing, a government lawyer told the Supreme Court on Tuesday.
“You could tomorrow decide that you put a GPS device on every one of our cars, follow us for a month. No problem under the Constitution?” asked Chief Justice John Roberts.
It is allowed under the court’s precedents, replied Deputy Solicitor General Michael Dreeben, and is no different than if the FBI “put its team of surveillance agents around the clock on any individual and follow that individual’s movements as they went around on the public streets.” But to many of the justices, something did seem different. In an intense hour-long exchange in which the Big Brother of George Orwell’s novel “1984” was referenced six times, the justices wondered how the dizzying pace of technology has changed a person’s reasonable expectation of privacy.
The justices pondered a world in which satellites can zero in on an individual’s house, cameras record the faces at a crowded intersection and people announce their every movement to the world on Facebook. They wondered about the government placing tracking devices in overcoats or on license plates.
“How do we deal with this?” Justice Samuel Alito asked. “Do we just say, ‘Well, nothing is changed,’ so that all the information that people expose to the public is fair game?”
The court is trying to apply the Constitution’s centuries- old protection against unreasonable searches and seizures at a time when devices such as a Global Positioning System can essentially do police officers’ work for them.
The case involves a suspected District of Columbia drug kingpin named Antoine Jones, who was convicted in part because of evidence gathered from the use of a GPS device placed on his car that tracked movements on public roads for 28 days.
His conviction was overturned when a panel of the U.S. Court of Appeals for the District of Columbia Circuit said the use of the GPS and extended period of surveillance required a warrant.
Other appellate courts have held that GPS surveillance does not require a warrant.
The justices displayed varying degrees of alarm about the government’s theory.
“If you win this case, then there is nothing to prevent the police or the government from monitoring 24 hours a day the public movement of every citizen of the United States,” Justice Stephen Breyer said.



