US Supreme Court

The U.S. Supreme Court ruled on Monday that police do not require a search warrant if they want to access cellphone location data held by mobile phone carriers. The case was filed by Quartavious Davis, of Florida, who is currently serving a nearly 162-year prison sentence relating to a string of Miami-area robberies that he participated in five years ago.

Davis appealed the convictions, arguing that police failed to obtain a search warrant before demanding location information from his cellphone provider, MetroPCS. The information obtained by police was crucial in linking Davis to seven crimes that occurred between August and October 2010. The robberies happened at a gas station, a Wendy's restaurant, a Walgreens drug store and other locations.

In a previous ruling in May, the 11th U.S. Circuit Court of Appeals decided that police were not required to obtain a search warrant, and Davis' Fourth Amendment protections from unreasonable searches and seizures had not been violated.

Prosecutors Use Cellphone Data to Convict Crime Suspects

Police can zero in on suspects' locations by analyzing cellphone location data to see what cellphone towers a specific person was connected to at specific times. The practice is being used by law enforcement officers to prove whether a suspect was near a crime scene at the time of a crime.

Lawyers from the American Civil Liberties Union (ACLU) represented Davis in his Supreme Court appeal. They argued that police require probable cause and a warrant to avoid a breach of the Fourth Amendment of the U.S. Constitution when requesting location data from cellphone providers.

The Supreme Court decided in Davis' case that, according to the federal Stored Communications Act of 1986, no search warrant is required, provided that prosecutors can (1) show "reasonable grounds" for requesting the information, and (2) show that the information is material and relevant to a particular investigation.

ACLU Says 1986 Act Did Not Anticipate Today's Reality

The ACLU argued that the Stored Communications Act of 1986 could not have predicted that mobile devices would be able to provide so much detailed information in the future.

This Supreme Court decision will likely affect similar civil rights cases over the privacy of cell site location information (CSLI), which are currently pending in lower courts throughout the nation. The case draws significant attention to the amount of privacy cellphone users can expect to have while using their devices.