[JURIST] The US Supreme Court [official website] ruled [opinion, PDF] Wednesday that police officers must obtain a warrant before searching a person’s cell phone data, even at the time of arrest. In Riley v. California and United States v. Wurie [SCOTUSblog backgrounders], the court considered the question of whether a search of cell phone data without a warrant violates a person’s Fourth Amendment [text] rights. Chief Justice John Roberts delivered the opinion for a unanimous court:

Modern cell phones are not just another technological convenience. 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. Our answer to the question of what police must do before searching a cell phone seized incident to an arrest is accordingly simple—get a warrant.

The court also held that while the police may not search the cell phone data, they may search the cell phone itself to make sure it cannot be used as a weapon. Justice Samuel Alito filed a concurring opinion, noting that he was not convinced that the rule on searches incident to arrest is based on the need to protect the safety of the arresting officers and the need to prevent the destruction of evidence.

In April the court heard arguments after it granted certiorari [JURIST reports] in January. Even though the two cases had similar subject matter, they were not consolidated. Riley concerns the petitioner’s smart phone being searched without a warrant, leading to the discovery of a photo that connected the petitioner to a shooting that occurred a few weeks before the petitioner’s arrest. Wurie had nearly the same subject matter except that the respondent’s flip phone was searched, leading to the discovery that he was in possession of a large amount of crack cocaine and a firearm. In both cases the defendants attempted to have the evidence seized from their cell phones suppressed, and both motions were denied. In the case of Riley, the California court of appeal upheld the denial of the petitioner’s motion, and the California Supreme Court [official website] refused to hear the case, whereas in the case of Wurie, the US Court of Appeals for the First Circuit [official website] reversed the denial of the petitioner’s motion.