In a unanimous ruling, the U.S. Supreme Court has decided that law-enforcement authorities need a warrant to track suspects using GPS devices placed by investigators.
However, the narrowness of the ruling means it probably will not affect future rulings on the legality of warrantless tracking of individuals' smartphones, or of built-in vehicle-navigation systems such as GM's OnStar. Four justices put forward a more expansive opinion that might have ended the not-uncommon practice of warrantless surveillance using cellphones, but failed to sway a fifth justice for a majority decision.
The justices ruled 9-0 to uphold a lower court decision that ruled that District of Columbia police and the FBI had violated the Fourth Amendment prohibition on arbitrary search and seizure in the case of Antoine Jones, a Washington, D.C. nightclub owner whom police suspected of drug dealing.
In 2005, D.C. police obtained a 10-day warrant to track Jones' wife's Jeep by placing a GPS tracker on the underbody of the vehicle. But the tracker was not placed until the 11th day, after the warrant had expired, and the device was attached to the car in Maryland, outside the warrant's jurisdiction.
Nonetheless, federal prosecutors were able to demonstrate that the Jeep traveled to known drug-distribution addresses within the next four weeks. To admit the GPS evidence, they successfully cited long-standing rulings supporting the "motor vehicle exception" to the Fourth Amendment, which argue that cars, trucks and buses traveling on public roads can be searched without a warrant.
Jones' first trial resulted in a hung jury, but he was convicted in 2008 and sentenced to life in prison.
In 2010, a federal appeals court struck down the conviction, arguing that the GPS evidence was inadmissible without a valid warrant. Today (Jan. 23), the Supreme Court agreed.
"The Government's attachment of the GPS device to the vehicle, and its use of that device to monitor the vehicle's movements, constitutes a search under the Fourth Amendment," states the Supreme Court decision, authored by Justice Antonin Scalia. "The Government physically occupied private property for the purpose of obtaining information."
That private property, Scalia wrote, was Jones' wife's Jeep, which Scalia argued is a personal "effect" as enumerated by the Fourth Amendment: "The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated."
"By attaching the device to the Jeep, officers encroached on a protected area," Scalia wrote.
Justice Sonia Sotomayor, who joined Scalia's opinion along with Chief Justice John Roberts and Justices Anthony Kennedy and Clarence Thomas, also wrote a concurring opinion of her own. She added to the view that the placing of the GPS device constituted trespassing.
"The Government usurped Jones' property for the purpose of conducting surveillance on him, thereby invading privacy interests long afforded, and undoubtedly entitled to, Fourth Amendment protection," Sotomayor wrote.
Central to Scalia's majority decision was a 1765 English ruling that considered a horse-drawn carriage a personal effect. Scalia equates the placing of the GPS device on the Jeep to a hypothetical 18th-century police constable hiding himself in a carriage, undetected by the occupants.
(In a second concurring opinion, which argues that Scalia's majority opinion does not go far enough, Justice Samuel Alito dismisses that argument in a footnote: "The Court suggests that something like this might have occurred in 1791 [when the Bill of Rights was written], but this would have required either a gigantic coach, a very tiny constable, or both — not to mention a constable with incredible fortitude and patience.")
But Sotomayor also bases her opinion on a 1967 Supreme Court case named Katz v. United States.
The Katz ruling held that police needed a warrant to wiretap a public pay telephone, because someone who used the pay phone and shut the phone-booth door would expect a "reasonable expectation of privacy" and hence was no longer in public.
"Situations involving merely the transmission of electronic signals without trespass would remain subject to Katz analysis," conceded Scalia, who refused to go further on that point.
Sotomayor did go further in her concurring opinion.
"With increasing regularity," wrote Sotomayor, "the Government will be capable of duplicating the monitoring undertaken in this case by enlisting factory- or owner-installed vehicle tracking devices or GPS-enabled smartphones.
"It may be necessary to reconsider the premise that an individual has no reasonable expectation of privacy in information voluntarily disclosed to third parties," she wrote. "This approach is ill suited to the digital age, in which people reveal a great deal of information about themselves to third parties in the course of carrying out mundane tasks.
"People disclose the phone numbers that they dial or text to their cellular providers; the URLs that they visit and the e-mail addresses with which they correspond to their Internet service providers; and the books, groceries, and medications they purchase to online retailers," Sotomayor wrote. "I for one doubt that people would accept without complaint the warrantless disclosure to the Government of a list of every Web site they had visited in the last week, or month, or year."
(We at SecurityNewsDaily are especially proud that Sotomayor cited an article by one of our contributing writers, John R. Quain, as evidence of such popular hesitation in her footnotes.)
Expectations of electronic privacy
However, history might have been made if Sotomayor had been persuaded to agree with the different concurring opinion authored by Alito, who enlisted Justices Stephen Breyer, Elena Kagan and Ruth Bader Ginsburg to his side.
Alito's opinion, which would have been a majority opinion with Sotomayor's vote, said the unanimous ruling doesn't go far enough. It argues that Katz should have been the entire basis for upholding the lower court's invalidation of Jones' conviction.
Scalia's majority opinion hinges on the physical placement of the GPS device, which, to him, constitutes trespass.
But to Alito, physical trespass is immaterial. The crux is, rather, whether the individual had a reasonable expectation of privacy. If so, then a warrant will always be necessary, whether or not the police add a tracking device.
"The Court's reasoning largely disregards what is really important (the use of a GPS for the purpose of long-term tracking)," wrote Alito, "and instead attaches great significance to something that most would view as relatively minor (attaching to the bottom of a car a small, light object that does not interfere in any way with the car's operation).
"If long term monitoring can be accomplished without committing a technical trespass — suppose, for example, that the Federal Government required or persuaded auto manufacturers to include a GPS tracking device in every car — the Court's theory would provide no protection," wrote Alito.
Had Alito's view been the majority view, it might have invalidated warrantless tracking of individuals via their cellphones or their built-in car-navigation systems.
Instead, the ruling leaves the legality of such situations to future decisions.