The Supreme Court today put an end to years of contentious debate over whether or not police can search the phones of people they arrest without first getting a warrant, ruling unanimously that law enforcement must always have a warrant before they can do the search.

As we mentioned back in January, there were two separate but related cases before court on this issue.

The first case, Riley v. California, involved whether or not evidence gathered from an arrestee’s phone without a warrant could be used against him in trial. Police arrested Riley in 2009 for attempted murder and assault with a deadly weapon after he shot at an occupied vehicle. He was later arrested and police searched the phone in his possession at the time, turning up evidence that identified him as a gang member out to kill members of a rival gang.
The phone also contained a photo of him with a car that had been spotted at the scene of the shooting. This, along with other evidence gathered from the phone was used against Riley in his trial, where he was convicted and sentence to 15 years behind bars. His lawyers contend that the warrantless search of his phone violated his Constitutional rights and this evidence should not have been used in trial.

The second case, United States v. Wurie, involved the 2007 arrest of a South Boston man (not Wurie) for allegedly dealing drugs out of his car. After he was taken into custody, officers found two phones on him. While police observed, one phone received several calls from Wurie, who they believed to be this dealer’s drug connection. The police reviewed the call log of this phone and tracked Wurie to his home. Wurie was ultimately convicted on drug distribution charges and sentenced to 262 months in jail. He appealed his conviction on the grounds that the phone search violated the Constitution, but the First Circuit Court of Appeals upheld the conviction.

The Riley case involved a smartphone while the Wurie case involved the search of an older flip phone. Some lower courts had held that police could search easily accessible information like call logs or address books on flip phones because they are not generally password protected. However, smartphones present a more complicated question, both because they often use some level of protection and because they contain significantly more information than a traditional cellphone.

Ultimately, SCOTUS combined both cases in issuing its opinion [PDF] on the matter.

The unanimous opinion, written by Chief Justice John Roberts, clarifies that the content on a person’s phone is protected against unwarranted search by the Constitution.

“Modern cellphones aren’t a technological convenience,” writes Roberts. “With all they contain and all they may reveal, they hold for many Americans ‘the privacies of life.'”

Many in law enforcement have argued that searching accessible information on an arrestee’s person is no different than checking their pockets for weapons or other evidence.

Roberts counters that searches of an arrestee’s pockets is both to protect evidence and for the arresting officer’s safety, but neither of those qualifications could be applied to a seized phone.

He cites the example of an officer who seizes what appears to be a pack of cigarettes from an arrestee. The officer observes while holding the cigs that what’s inside the package is not cigarettes.

“Given that, a further search was a reasonable protective measure,” writes Roberts, adding that “No such unknowns exist with respect to digital data” and that the officers who arrested Wurie “knew exactly what they would find therein: data. They also knew that the data could not harm them.”

The court held that there was no problem with seizing the either Riley’s or Wurie’s phones; it was the warrantless searches of these devices that caused the problems.

With regards to concerns from law enforcement that a third party might attempt to remotely wipe or scramble an arrestee’s phone before a warrant could be obtained, Roberts questioned the likelihood of that happening, saying that attorneys could only provide a few examples of an arrest ever triggering a remote wipe.

“Moreover, in situations in which an arrest might trigger a remote-wipe attempt… it is not clear that the ability to conduct a warrantless search would make much of a difference,” writes the court. “The need to effect the arrest, secure the scene, and tend to other pressing matters means that law enforcement officers may well not be able to turn their attention to a cell phone right away.”

Wurie’s conviction was vacated by the First Circuit Court of Appeals. Today’s decision affirms that ruling. The Riley case has been remanded to the California Court of Appeal.

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