WASHINGTON D.C. —­­ Today, the Supreme Court ruled that a warrant is required for the government to access cell-site location information (CSLI) on a person’s cell phone. The 5-4 decision in Carpenter v. United States declared that accessing such information is a Fourth Amendment search, which requires a warrant supported by probable cause. The Supreme Court reversed and remanded a decision by the Sixth Circuit Court of Appeals, which held that a person did not have a reasonable expectation of privacy in cell phone location data that had been shared with a wireless carrier.

“The Carpenter decision is a great victory for Americans’ privacy rights” said Ashkhen Kazaryan, Legal Fellow at TechFreedom. “This ruling recognizes the immensely sensitive nature of cell phone location data, and rightly requires a showing of probable cause before law enforcement can obtain location information from mobile carriers. Our country’s Founders would have expected no lesser safeguards to apply to non-stop surveillance. Indeed, the American Revolution was first instigated over surveillance that was far less invasive.”

Chief Justice Roberts’s majority opinion, joined by Democratic appointees Justices Sotomayor, Ginsburg, Breyer and Kagan, noted:

A cell phone faithfully follows its owner beyond public thoroughfares and into private residences, doctor’s offices, political headquarters, and other potentially revealing locales. Accordingly, 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. … Before compelling a wireless carrier to turn over a subscriber’s CSLI, the Government’s obligation is a familiar one—get a warrant.

“After decades of confusion over how to deal with digital technologies, the Supreme Court is now finally making clear how what privacy rights apply in the Digital Age,” concluded Kazaryan, noting the Court’s decisions in Jones (2012), Riley (2014), and Carpenter. “Even though this decision was narrowly tailored to the fact pattern of the case presented, the Court cleared a way for future cases to provide the same level of protection to all of our highly personal digital footprint. Moving forward, law enforcement will no longer win on the argument that using technology as commonplace as mobile phones means giving up your Fourth Amendment rights.”


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