Supreme Court Bolsters Mobile-Phone Privacy Rights

The U.S. Supreme Court ruled in a decision that bolsters digital privacy rights of cellphone users. In a 5-4 vote, the court ruled law enforcement needs a warrant to obtain mobile phone tower records that can reveal a user’s location over time.

The ruling was made on Friday in a case involving Timothy Ivory Carpenter, who attorneys argued had his Fourth Amendment rights violated when law enforcement officials obtained four months of phone data. Cellphone data was then used in a trial to show Carpenter was close in proximity to a string of armed robberies.

Privacy activists are applauding the decision and believe the ruling will have a far-reaching impact on related Fourth Amendment cases. The Fourth Amendment protects citizens from unreasonable search and seizure. As a direct result of this ruling, law enforcement would have to go to a court and present a judge with a “first showing of probable cause” as a precursor to getting a warrant to request mobile phone data, such as what cell towers a user connected to and when.

In thousands of cases a year, cellphone metadata is obtained from mobile-phone carriers without probable cause or a warrant by law enforcement.

“We decline to grant the state unrestricted access to a wireless carrier’s database of physical location information,” wrote Chief Justice John Roberts in his majority opinion in the case Carpenter v. United States (PDF). He was joined by the four Democratic Supreme Court appointees. Dissenting were Justices Anthony Kennedy, Clarence Thomas, Samuel Alito and Neil Gorsuch.

The court said the decision was a narrow one and that issues involving “conventional” surveillance tools such as security cameras were not applicable. “This decision is narrow… [It does not] call into question conventional surveillance techniques and tools, such as security cameras; does not address other business records that might incidentally reveal location information; and does not consider other collection techniques involving foreign affairs or national security,” according to the majority justices.

Lawyers representing Carpenter, which included those from the American Civil Liberties Union, had argued that cellphone location data constituted sensitive data that deserved Fourth Amendment protection.

On Friday, ACLU attorney Nathan Freed Wessler issued a statement:

“This is a groundbreaking victory for Americans’ privacy rights in the digital age. The Supreme Court has given privacy law an update that it has badly needed for many years, finally bringing it in line with the realities of modern life. The government can no longer claim that the mere act of using technology eliminates the Fourth Amendment’s protections.”

Sen. Ron Wyden, a Democrat from Oregon, also chimed in with the release of a statement:

“Today’s ruling strikes a blow against the creeping expansion of government intrusion into the most personal parts of Americans’ lives. The court’s recognition that digital devices can generate ‘near-perfect surveillance’ of a person’s private life is a validation of the vital protections against unreasonable search and seizure provided by our Constitution.”

Wyden and others have fought for stricter policies around phone location data. Last month, Wyden and others expressed concern over a service offered by Securus Technologies that allowed law enforcement to monitor people’s phones and track their location. The company buys real-time location information from major wireless carriers under the premise that the information could be used for targeting mobile ads.

“I have argued for years that the sheer volume of information about every single American that is collected by our phones and computers requires a fundamental rethinking of the idea that giving your information to a company means the government can get it too,” Wyden’s statement continued.