The justices said they also wanted to hear argument on whether the installation of a GPS device without a valid warrant violates the 4th Amendment. The court should hear argument in the case next term.
GPS provides the location of a device and the timing of its movements anywhere on the globe, even in bad weather, as long as the device is able to fix on four or more GPS satellites in orbits maintained by the U.S. government.
The private sector and the military use GPS for a variety of purposes and its use by law enforcement is widespread.
In 2004, a joint Safe Streets Task Force of the FBI and Washington police focused on Antoine Jones, who owned and operated a nightclub in the District of Columbia and was suspected of narcotics violations.
In addition to a variety of techniques designed to link Jones to his alleged co-conspirators and to illegal drugs, agents also obtained a warrant from a federal judge authorizing them to secretly install and monitor a GPS tracking device on Jones' Jeep Grand Cherokee -- as long as it was installed within 10 days and only within the District of Columbia.
But the agents did not install the device until 11 days after the warrant was issued, and while the Jeep was parked in a public parking lot in Maryland, not the district.
In October 2005, court records said, agents executed search warrants at various locations, recovering large amounts of cash, cocaine, drug paraphernalia and firearms and Jones was indicted.
Before trial, Jones' lawyers moved to suppress the data from the GPS tracking device. A federal judge ruled that any information gleaned while the Jeep was on public roads was admissible.
The jury acquitted Jones of some charges and was unable to reach a verdict on others.
Then a new federal grand jury, in a superseding indictment, charged Jones with a single count of conspiracy to distribute and possess 5 kilograms of cocaine and 50 grams or more of cocaine base.
After a second trial in which prosecutors used GPS information, Jones was convicted of the sole count. A judge sentenced him to life in prison and ordered him to forfeit $1 million in proceeds from drug trafficking.
But the U.S. Court of Appeals for the District of Columbia reversed the conviction, saying Jones had a reasonable expectation of privacy in the public movements of his Jeep over the course of a month because he had not exposed the "totality" of those movements to the public -- "the whole of a person's movements over the course of a month is not actually exposed to the public because the likelihood a stranger would observe all those movements is essentially nil."
The U.S. Justice Department asked the Supreme Court for review.