By Alison Frankel

David Riley was already in deep trouble when the San Diego Police Department got hold of his Samsung smartphone in August 2009. Riley had been driving around the neighborhood in a Lexus with expired tags, and when he was pulled over police discovered that his license had been suspended. They searched his car and found guns hidden under the hood. Riley was arrested for carrying concealed and loaded weapons.

But it was the smartphone that sank him. At the arrest site, police scrolled through Riley’s text messages and contacts, finding what they considered to be indications that Riley was a member of the Bloods gang. Hours later, when he was under interrogation at the police station, a gang expert conducted a second search of Riley’s phone. He found photos and videos that, according to police, tied Riley to a gang-related drive-by shooting. Despite defense arguments that the smartphone seizure violated Fourth Amendment strictures on warrantless searches, prosecutors later used a photo and videos taken from Riley’s phone at his trial, which ended with his conviction for shooting at an occupied vehicle and two other charges. And because the smartphone supposedly linked Riley to gang activity, he was subject to an enhanced sentence. Instead of a maximum of seven years, he was sentenced to a prison term of 15 years to life.

The California Supreme Court declined to hear Riley’s Fourth Amendment appeal earlier this year, presumably because the state high court had already determined, in a 2011 case called Diaz v. California, that police may conduct warrantless searches of cellphones when the phones are seized from a person under arrest. On July 30, Riley’s lawyers at Stanford’s Supreme Court Litigation Clinic and Goldstein & Russell petitioned the U.S. Supreme Court to take his case. “This is the leading privacy issue, the next big technology and Fourth Amendment issue everyone is watching,” said Riley’s lead appellate counsel, Jeffrey Fisher of Stanford. “Now it has come to a crescendo.”

The question of whether police can search cellphones they seize during arrests is, in fact, so hot that Riley’s certiorari petition isn’t the only one raising the issue at the Supreme Court. Two weeks after Riley’s filing, the Justice Department asked the high court to review Wurie v. U.S., a 2013 decision by the 1st Circuit Court of Appeals that squarely conflicts not only with the 2011 California Supreme Court decision that doomed Riley but also with rulings by two other state Supreme Courts and three federal circuit courts. Both the Justice Department and Riley petitions argue that the high court must step in to reconcile contrary rulings that have left police departments and prosecutors without clear guidance on defendants’ Fourth Amendment rights to shield their phones from warrantless searches. It seems inevitable that the Supreme Court will eventually have to decide the question, but first the justices will have to figure out whether Riley’s case or the Justice Department’s (or both) is the best vehicle to clarify the law.

The defendant in the Justice Department case, Brima Wurie, was arrested back in 2007, before smartphones became commonplace. Police seized Wurie’s more basic flip-style cellphone after arresting him for selling two bags of crack cocaine. From a limited search of the phone, the government was able to figure out Wurie’s home address (he had given them a false address) and to obtain a warrant to search the house. That search turned up the drug stash at the heart of Wurie’s conviction in federal court in Boston.

On appeal, Wurie raised the same Fourth Amendment defenses as Riley, with drastically different results. In May 2013, the 1st Circuit overturned his conviction, holding in a 2-to-1 decision that the search of Wurie’s phone violated the Fourth Amendment so all evidence stemming from that search must be suppressed. The ruling established what the appeals court called a “bright line rule” that government officials may not conduct warrantless searches of cellphones seized from defendants under arrest.

The 1st Circuit’s opinion explicitly noted that its holding contradicts rulings by the 4th, 5th and 7th Circuits, which have all concluded that cellphones seized during arrests may be searched without a warrant under the U.S. Supreme Court’s precedent in U.S. v. Robinson and U.S. v. Edwards. Those cases, which both date from the early 1970s, carved out an exception to the Fourth Amendment’s bar on warrantless searches for clothes and other items – including such things as briefcases and address books – seized “incident to arrest” on the defendant’s person or in the immediate vicinity. (The principal justification for the exception is that it’s reasonable for police to search for weapons or evidence during an arrest.) State courts are also divided on warrantless cellphone searches: Courts in Florida and Ohio have recently agreed with the 1st Circuit that such searches violate the Fourth Amendment, but high courts in California and Massachusetts have deemed cellphone searches legal under Robinson and Edwards.

The government’s petition for Supreme Court review of the Wurie case focuses on the direct split between the 1st Circuit and the Massachusetts Supreme Court, which leaves state law enforcement in a quandary. Interestingly, the Justice Department petition only obliquely addresses the Riley case, arguing that the record in Wurie, but not in Riley, raises an alternative argument that the search of Wurie’s phone was justified by police officers’ reasonable belief that the defendant was lying about his home address. For the government, which would like the Supreme Court to bless warrantless cellphone searches, Wurie is probably a better case than Riley because the officers who searched Wurie’s phone conducted a very limited examination, not a deep dive into Wurie’s photos and phone history.

Riley – and four quite diverse groups that filed friend-of-the-court briefs at the Supreme Court last Friday – argue that smartphones offer the government much broader access to information than the flip phone Wurie used, so Riley’s case provides a starker example of the consequences of warrantless phone searches. An increasing percentage of cellphones, they assert, are smartphones, which contain not only text and phone records but Internet search history and, in apps, all manner of additional business and personal information. The data contained on a smartphone, wrote Mayer Brown in an amicus brief for the Center for Democracy & Technology and the Electronic Frontier Foundation, far exceeds the information that could be contained in paper files a person might have carried at the time of the Supreme Court’s rulings in the 1970s on warrantless seizures. Those rulings, according to Riley’s amici, could not have anticipated that police could gain access without a warrant to the array of personal data available on smartphones. The amicus brief of the Constitutional Accountability Center goes so far as to argue that warrantless cellphone searches are akin to the despised Colonial-era general warrants that inspired drafters of the Constitution to include the Fourth Amendment’s protections against unreasonable search and seizure.

“This issue applies to everyone, from a corporate executive to a teenaged drifter,” said Riley counsel Fisher, who pointed out that one of the precedential rulings on warrantless cellphone searches involved a businessman whose phone was seized when he was arrested for drunk driving.

Fisher said he’s “not in the business of predicting what the Supreme Court will do,” but said the justices signaled an interest in the intersection of technology and the Fourth Amendment in their ruling in the 2012 case of United States v. Jones, in which a unanimous court said that warrantless GPS tracking violates the Fourth Amendment. “There’s every reason the court will carry the same sensitivity to this case,” Fisher said.

The Riley case was scheduled for consideration by the Supreme Court justices later this month, but on Tuesday the court asked to hear from the state of California. That brief is due on Oct. 3. Wurie’s response to the Justice Department’s cert petition is due in mid-September. According to Riley counsel Fisher, the justices will probably not conference on the cases until November.