IN RILEY V. California (2014), the U.S. Supreme Court held that law enforcement officials had violated the Fourth Amendment when they searched an arrestee's cellphone without a warrant. "Modern cell phones are not just another technological convenience," Chief Justice John Roberts wrote for the majority. "With all they contain and all they may reveal, they hold for many Americans 'the privacies of life.' The fact that technology now allows an individual to carry such information in his hand does not make the information any less worthy of the protection for which the Founders fought."
The requirement to get a warrant may not apply, however, when an American citizen is returning home from abroad and U.S. border officials want to search the contents of that person's phone--at least according to a decision issued in March by the U.S. Court of Appeals for the 11th Circuit.
Hernando Vergara, a U.S. citizen, was returning home from a cruise to Mexico. Because of a prior criminal conviction, a Customs and Border Protection officer searched his luggage, including the three cellphones that Vergara was carrying. One of those phones contained "a video of two topless female minors."
At that point, the Department of Homeland Security stepped in. Vergara's phones were taken away to a government facility, where they were subjected to a warrantless forensic search, a process that typically involves retrieving deleted files and other...