Law enforcement officials cannot track people’s whereabouts using mobile phone location records without first obtaining legal authorisation, the US Supreme Court decided.
In a legal case (Timothy Ivory Carpenter versus the United States), the government argued location information kept by mobile operators was not covered by the country’s Fourth Amendment, which protects citizens against unreasonable search and seizure, because the data was held by third parties.
But the court disagreed, noting in its ruling the constitutional protections do apply “given the unique nature of cell phone location records”, albeit by a slender vote of five for versus four against by the panel of nine judges.
It concluded allowing government free reign to access cell site records without demonstrating the “probable cause” required for a warrant violates the public’s reasonable expectation of privacy.
“When the government tracks the location of a cell phone it achieves near perfect surveillance, as if it had attached an ankle monitor to the phone’s user…Only the few without cell phones could escape this tireless and absolute surveillance.”
However, the court stressed the ruling does not apply to conventional surveillance tools, such as security cameras, nor does it address “other business records that might incidentally reveal location information”.
The case was closely watched by the industry as the latest in a series of digital privacy decisions from the court.
In 2014, the Supreme Court unanimously ruled law enforcement officials need a warrant to search a person’s mobile device.