• Justice Breyer questions phone encryption and 'brzzing' sounds • Yochai Benkler: court needs to keep up with our cellphones

Civil liberties lawyers on Tuesday warned that police seizure of smartphones is becoming a grave threat to US privacy, in a supreme court hearing that saw the world of Facebook, Fitbits and cellphone encryption collide with centuries-old jurisprudence.

The nine justices struggled with two cases that sought to establish whether police can search digital content from seized cellphones in the same way they are allowed to handle physical diaries or photographs held by someone at the time of their arrest.

Several justices questioned why a warrant would be any more necessary in the case of digital content than it is for physical possessions, which can be seized to check for weapons or prevent the destruction of evidence.



“What is the difference between [photos stored on a smartphone and] hard copy photos in a billfold?” asked justice Samuel Alito. “I don't see there is much of a difference,” he added.



But lawyers for two test cases, supported by the American Civil Liberties Union and Electronic Privacy Information Center, argued the scale of digital information now stored by many people on their phone made it more analogous to private diaries and letters kept at home, which are protected from unwarranted searches under the fourth amendment.



“It is not just what can be looked at, it is how it can be kept,” said Jeffrey Fisher, who was acting for David Riley, a San Diego college student incriminated by photos found on his phone after his car was stopped for having expired licence plates. “They are keeping this information in ever-growing databases.”



Fisher warned that minor driving offences could “open up every American's life” to the police and that existing case law dealing with physical possessions was inadequate to capture the privacy risks of the digital age.



“The reason you don't find diary cases is because people hardly ever carry a diary with them,” he argued. “The reality of a smartphone is that it is an indispensable item.”



The argument was better received by some on the bench, who accepted it was a world out of many of their personal experiences.



“A person could be arrested for driving without a seatbelt, police can take the phone, look at their work emails … look at their bank details, look at GPS data and find out where that person had been,” said Justice Elena Kagan. “That strikes me as a very different type of world to one where a person has photos in a billfold.”



“People carry their entire lives on cellphones,” she added. “That is not a marginal case; that is the reality … Most people carry their lives on cellphones and that will only grow every year as young people take over the world. Everyone under a certain age – let's say under 40 – has everything on them.”



But other judges on the bench appeared to argue that young people were acknowledging a lower standard of privacy by carrying such data around with them and posting it on social networking sites.



Does this “includ[e] information that is designed to be public?” asked Chief Justice John Roberts. “What about Facebook and Twitter? … It is certainly not private in the way people's things are.”



Roberts also asked whether police could check a person's movements by examining their Fitbit exercise monitor or review their banking apps for financial data. “Carrying [personal data] with you in public makes it less private,” he added.

Justice Stephen Breyer said he believed “there are very few cases that you can't find analogues in the pre-digital age” and gave an example of how bits of paper held by suspects might be equivalent to data from GPS satellites.



“I don't want to admit that my wife might have put a little note in my pocket 'Stephen, turn right at the third stop sign,'” he said.



Later he appeared to bemuse lawyers by referring to the “brzzing” sound of phones and “buzzers” you can push. “[What if] they can just cough and encrypt it?” asked Breyer when discussing why seizing a phone might not be enough to prevent evidence tampering.



When one lawyer started a response by saying “I don't know what kind of smartphone you have, perhaps an iPhone,” Breyer responded: “I don't know either because I can never get into it because of the password.”



The issue of password protection and data encryption was an issue of particular concern to lawyers representing law enforcement agencies in the two cases.



“It is an arms race between the forensic capabilities of our enforcement labs and the ability of technology companies and criminals to devise technology that will thwart that,” said Michael Dreeben, deputy solicitor general at the Department of Justice.



He also revealed the FBI had been frustrated in an attempt to store seized cellphones in a protective Faraday cage because they discovered Verizon had installed a cell tower on the roof.



A narrow majority of justices appeared to side with Dreeben's suggestion that the court settle on a rule that applies to “information of the same sort as people have always been able to seize: diaries, letters, photos”.



Although Justice Ruth Bader Ginsburg expressed “nervous concern” that a misdemeanour might “open the world to police”, her colleague Anthony Kennedy countered that “criminals are more dangerous and elusive with smartphones.”



“The same rules should apply … the digital format does not change [matters],” concluded Dreeben.

