The Supreme Court agreed to hear a significant privacy rights case on Monday, Carpenter v. United States, which centers on whether the police must get a warrant to obtain historical cellular telephone data to determine a person’s movements or location.
Network provider companies collect vast amounts of increasingly detailed information through texts, calls, and other data sent through a cellular network. The data includes identifying information that can provide accurate details about location at the time of use.
Carpenter focuses on if cellphone users can expect personal data to be covered by the Fourth Amendment’s protection against unreasonable search and seizure.
Police used a federal statute under the Electronic Communications Privacy Act of 1986 to obtain more than five months of cellphone data on Michigan robbery suspect Timothy Carpenter rather than receive a warrant from a judge. To get a warrant for the data required establishing probable cause, a more difficult standard to meet compared to the federal law.
Officers received data from 127 days, identifying over 12,800 different locations for Carpenter during the investigation period without a warrant. Carpenter’s conviction was based on his cell phone location data.
The American Civil Liberties Union is defending Carpenter and said in a statement that this case shows how cellphone location data, “can reveal extraordinarily private details about people’s lives, from where they sleep to where they pray.” According to the ACLU, police seek cellphone location records tens of thousands of times each year.
“The time has come for the Supreme Court to make clear that the longstanding protections of the Fourth Amendment apply with undiminished force to these kinds of sensitive digital records,” Nathan Freed Wessler, an ACLU attorney, said.
The U.S. Court of Appeals for the 6th Circuit in April sided with the police in the initial review. They found cellphone users have no reasonable expectation of privacy regarding cellphone location data held by mobile service providers.
Investigating police sought information that people knowingly expose to the mobile service companies such as routing information maintained by the providers. One 6th Circuit judge, however, wrote, “the sheer quantity of sensitive information procured without a warrant” raises Fourth Amendment concerns.
The government argued the Supreme Court should not review the case as it contends the procedure used by investigators in the case is constitutional. Given that laws governing cell phone location data vary by state the ACLU hopes a review will establish legal guidelines for police across the country.
[Roll Call] [CNET] [ACLU.org]