Do cops need a warrant to search your phone? US Supreme Court will rule

The US Supreme Court on Friday agreed to hear a pair of cases to determine whether police need a warrant to search the mobile phones of people they have arrested.

The Fourth Amendment to the US Constitution forbids "unreasonable" search and seizure, but in 1973 the Supreme Court ruled that conducting a full search of an arrestee's person and belongings was not unreasonable, even without a search warrant.

That was long before the smartphone era, however, and in more recent cases, various state and federal courts have been divided as to whether downloading the contents of a phone is the same thing as, say, looking inside a pack of cigarettes.

Appeals to the Supremes to decide the matter have come from both sides of the fence.

In one case, attorneys for David Leon Riley, a California man serving a 15-year sentence for attempted murder and other crimes, are seeking to invalidate photos, videos, and other evidence presented during his trial that police obtained from his phone without a warrant.

In convicting Riley, the court ruled that "the cell phone, which as I understand it was on [Riley's] person at the time of the arrest, would fall into the category of a booking search, the scope of which is very broad." An appeals court later upheld [PDF] that decision.

But in a separate case involving a conviction for drug sales in Massachusetts, the US First Circuit Court of Appeals sided with the defendant, arguing that law enforcement's authority to search mobile phones isn't so cut and dried.

"Today, many Americans store their most personal 'papers' and 'effects' ... in electronic format on a cell phone, carried on the person," the court wrote in its decision. "Allowing the police to search that data without a warrant any time they conduct a lawful arrest would, in our view, create 'a serious and recurring threat to the privacy of countless individuals.'" Prosecutors are hoping the Supreme Court will disagree.

In an order [PDF] issued on Friday, the high court agreed to hear both cases, although in Riley's case it said it would only hear arguments on whether the search of Riley's mobile phone violated his Fourth Amendment rights.

Notably, the court did not consolidate the two cases, which presumably means they will be argued and decided separately.

How the Supremes ultimately rule could have broad implications beyond searches of phones. In the Massachusetts case, the court observed, "The government admitted at oral argument that its interpretation of the search-incident-to-arrest exception would give law enforcement broad latitude to search any electronic device seized from a person during his lawful arrest, including a laptop computer or a tablet device such as an iPad."

The Supreme Court is expected to hear both cases in April. ®