It was a scary prospect that we wrote about before: Police didn't need a warrant to search your smartphone. They only needed to have probable cause to arrest you. If your phone was with you, all its contents was theirs for the browsing.

The U.S. Supreme Court, in weighing a Southern California case, said that's no longer true: Search warrants are necessary except in exigent emergencies.

The case involved a San Diego gang member who was stopped by police in 2009 for expired registration. Somehow cops got under the hood of the suspect's Lexus and found two guns. That put the man under arrest, and that put his phone in the hands of the police:
The Samsung smartphone contained photos that police say proved the man, 23-year-old David Riley, was involved in an earlier shooting in the Skyline district of San Diego. Despite his lawyer's protestations, Riley ultimately went down for attempted murder.

The Supreme Court's opinion could end up overturning his conviction.

The decision was unanimous. It sends Riley's case back to a California appeals court, which will likely consider whether a lack of smartphone evidence would cancel the prosecution's case. 

Chief Justice John Roberts wrote the Supreme Court's opinion. He said, in part:

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.

Police had argued that they get to rifle through pockets and wallets when suspects are arrested to ensure their own safety in case weapons are present. They said the practice should be extended to going through the data on a suspect's cellphone.

Credit: K?rlis Dambr?ns/Flickr

Credit: K?rlis Dambr?ns/Flickr

The high court said cellphone snooping contained “an element of pervasiveness.” It noted that we keep more than phone records on our devices – we store detailed, intimate records of our lives on them: “They could just as easily be called cameras, video players, rolodexes, calendars, tape recorders, libraries, diaries, albums, televisions, maps, or newspapers.”

In San Diego, sheriff's deputies were encouraged to use software to download everything on a suspect's smartphone so that it could be searched.

No longer. Te San Diego U-T reported that it would take at least an hour to get a judge's permission to search a cellphone.

The American Civil Liberties Union praised the Supreme Court's decision. Steven R. Shapiro, national legal director of the group, said:

By recognizing that the digital revolution has transformed our expectations of privacy, today's decision is itself revolutionary and will help to protect the privacy rights of all Americans. We have entered a new world but, as the court today recognized, our old values still apply and limit the government's ability to rummage through the intimate details of our private lives.

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