On June 25, 2014, in Riley v. California, the United States Supreme Court unanimously held that law enforcement officers may not view data contained in mobile devices without a warrant. In his Opinion of the Court, Chief Justice John Roberts recognized that the Fourth Amendment’s prohibition of unreasonable searches and seizures offers meaningful, broad privacy protections in the digital age. The Court’s decision offers a clear, bright-line boundary of protection for personal data.

Riley signals the Court’s willingness to consider the realities of modern technology in daily life when applying constitutional privacy protections. In its opinion, the Court scoffed at the government’s suggestion that searching data on mobile devices is no different than permissible warrantless searches of wallets and purses following an arrest, commenting that the argument “is like saying a ride on horseback is materially indistinguishable from a flight to the moon. Both are ways from getting from point A to point B, but little else justifies lumping them together.” In noting the differences between searches of physical items such as wallets and purses and digital items such as cell phones, the Court concluded that digital searches are much more intrusive and thus deserve more protection. Rileyrecognizes that mobile phones are not just phones, but also can be “cameras, video players, rolodexes, calendars, tape recorders, libraries, diaries, albums, televisions, maps, or newspapers.” As such, the vast amounts and varied types of information they hold is generally much more private than what can be gleaned from the non-electronic contents of an arrestee’s pockets, wallet or purse.

In a concurring opinion, Justice Samuel Alito recognized that the Court’s bright-line rule provides more privacy protection for electronic information than its non-electronic counterparts. Justice Alito noted that a paper phone bill containing phone records, if seized from the pocket of an arrestee, could lawfully be searched without a warrant, while the same call-log data stored on an arrestee’s mobile phone could not. Still, Justice Alito agreed that because “law enforcement officers need clear rules regarding searches incident to arrest,” the Court should protect privacy interests by banning all warrantless searches of cell phones. The Riley decision is a victory for privacy advocates, and may signal a broader willingness by the Court to adopt clear, strong protections for personal data stored electronically.