Newsflash: Supreme Court Must Affirm Privacy Protections for Cell Phone Data

August 14, 2017

The Supreme Court should recognize that cell phone location data is private information deserving of full Fourth Amendment protection, according to a brief filed today by the Brennan Center for Justice at NYU School of Law, Electronic Frontier Foundation, Constitution Project, National Association of Criminal Defense Lawyers, and National Association of Federal Defenders. Even in limited quantities, cell phone location information can be a telltale sign of private social, political, and religious activities protected by the Constitution.

The brief argues that “third-party doctrine,” which negates privacy protections for data held by a third-party service provider, should not apply to cell phone location information. The doctrine predates the existence of cell phones, and is a poor fit for the digital age, in which Americans generate staggering amounts of third-party data simply by carrying a cell phone.

“Cell phone location information has such significant implications for freedom of speech and association that it demands full Fourth Amendment protection, no less than the private papers in your desk drawer,” said Michael Price, senior counsel in the Brennan Center’s Liberty & National Security Program. “If law enforcement wants to access cell site location information, it should get a warrant.”

Read the full amicus brief.

Read more about the case Carpenter v. United States, currently before the U.S. Supreme Court.

Read more about the Brennan Center’s work on Liberty & National Security.

For more information or to schedule an interview, contact Naren Daniel at (646) 292-8381 or