In a broad, unanimous decision, the Supreme Court ruled on Wednesday that police must have a warrant before searching a cellphone belonging to a person who’s been arrested.The ruling was particularly striking for the extent to which the Court went in affirming the idea that technological change demands a reconsideration of privacy protections—an assertion that could have big implications in the debate about the government’s data collection programs.
“Modern cellphones are not just another technological convenience. With all they contain and all they may reveal, they hold for many Americans ‘the privacies of life,’” wrote Chief Justice John Roberts. “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.”
The ruling covered two cases in which police used information found on arrestees’ cellphones to tie them to a crime. In the first, David Riley was pulled over for driving with expired registration tags, and was subsequently found to have a suspended license and concealed handguns under the hood of his car. When officers searched the smart phone in his back pocket they discovered photos and other information tying him to the Bloods gang. Police traced the guns to an earlier shooting, for which Riley was later convicted; his prison sentence was “enhanced” because of his gang connection.
In the second case, police officers searched a regular flip phone belonging to a man named Brima Wurie, who’d been observed making a drug deal. Officers traced a number listed in Wurie’s phone as “my house” to an apartment complex, which they obtained a warrant to search, finding crack cocaine, weapons and cash.
Both plaintiffs argued that the warrantless phone searches violated their Fourth Amendment rights to be “secure in their persons, houses, papers or effects.” Legal precedent has granted police some leeway for searching an arrestee and the area within his reach, primarily to check for weapons and to keep evidence from being destroyed. But privacy advocates argued that because cellphones now contain vast troves of personal data—“well over a football field’s length of books” in some cases, according to one brief—searching them constitutes a breach of privacy serious enough to demand a warrant.
The Court concurred. “The sum of an individual’s private life can be reconstructed through a thousand photographs labeled with dates, locations, and descriptions; the same cannot be said of a photograph or two of loved ones tucked into a wallet,” Roberts wrote. “Indeed, a cell phone search would typically expose to the government far more than the most exhaustive search of a house.”
According to the ruling, police may inspect a phone to make sure it’s not concealing a weapon, but generally they may not look through its contents without a warrant.
The fact that the Court passed over several suggested rulings that were much more limited in their defense of civil liberties is particularly striking. There was some speculation that the Court might make a distinction between the two cases based on the type of phone, and create separate rules for searches of smart phones and conventional phones. The Court rejected such a distinction, as well as the government’s suggestion that officers be allowed to search phones in cases where they believe it contains evidence of the crime for which its owner was arrested, or that they only be allowed to search areas of the phone which they “reasonably” believe to have information about a crime. In a blunt rebuke, Roberts argued that those standards “would prove no practical limit at all when it comes to cellphone searches.”
Beyond criminal justice, the ruling may have significant implications for the government’s surveillance activities. A thirty-five-year old Supreme Court ruling known as Smith v. Maryland, which found that records held by a third party (like a phone company) are not protected by the Fourth Amendment, has been used to justify many forms of surveillance, including tracking a cellphone’s location and the National Security Agency’s dragnet phone records program. In recent years, several judges have argued that the precedent set by Smith does not make sense in the digital age.
The Supreme Court’s ruling on cellphone searches casts yet more doubt on Smith’s role in the age of big data. Based on the Smith ruling, the government had argued that officers should always be able to search a phone’s call log, just as they searched Wurie’s. The Court resoundingly rejected that suggestion: “There is no dispute here that the officers engaged in a search of Wurie’s cell phone. Moreover, call logs typically contain more than just phone numbers; they include any identifying information that an individual might add, such as the label ‘my house’ in Wurie’s case.”
Critics of government surveillance were quick to note the ruling could be significant in the debate over data collection. “The next step, in my view, is to treat GPS information the same way,” Senator Ron Wyden said in a statement. “I aim to use this decision as a springboard to secure greater privacy rights in the days ahead.”
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