Prior results do not guarantee a similar outcome.

The Supreme Court of the United States (SCOTUS) handed down a landmark decision in Carpenter v. United States on June 22. 2018 regarding cell-site location information (CSLI). SCOTUS ruled that law enforcement must secure a search warrant based on probable cause in order to acquire CSLI.

Cell phones are an indispensable part of most Americans’ lives. There are 396 million cell phone service contracts in the United States, a country whose population is 326 million people. In its simplest terms, cell phones connect to a set of radio antennas called cell sites. Each time a cell phone connects to a cell site, it generates a time stamped record known as CSLI.

In Carpenter, the petitioner Timothy Carpenter was convicted of six counts of robbery and five counts of carrying a firearm during a federal crime of violence related to a series of robberies of Radio Shack and T-Mobile stores in Detroit. He was sentenced to more the 100 years in prison. The prosecution’s case was supported by obtaining CSLI for Mr. Carpenter’s cell phone. This information demonstrated that Mr. Carpenter was at the scene of every robbery.

The prosecution was able to obtain Mr. Carpenter’s CSLI by applying for court orders under the Stored Communications Act. The standard required to obtain the order was reasonable grounds to believe that the records sought are relevant and material to an ongoing criminal investigation. Mr. Carpenter appealed his conviction and the issue ultimately was granted certiorari by SCOTUS.

SCOTUS ruled the Fourth Amendment protects not only property interests but certain expectations of privacy as well. One of those expectations of privacy is the privacy in the whole of their physical movements. Allowing the government to access CSLI contravenes that expectation of privacy. As such, SCOTUS ruled that, absent case specific exigent circumstances such as pursuing a fleeing suspect, protecting individuals threatened with imminent harm, or to prevent the destruction of evidence, the Government must demonstrate probable cause to obtain a search warrant for CSLI, reversed Mr. Carpenter’s convictions and remanded the case for further proceedings.