In a surprisingly forceful decision, the Supreme Court on Wednesday unanimously ruled that police may not search the digital contents of an arrested person's cell phone before obtaining a warrant.
The sweeping opinion is seen by privacy advocates as a substantial victory in the fight against government's tightening grip on the private, digital communications of U.S. citizens, and could be a precursor to how the Court handles other questions regarding government surveillance, an issue that has been at the forefront of international policy debates since the Edward Snowden leaks first surfaced last June.
Chief Justice John Roberts, writing for the Court, said the contents of a person's phone are protected under the Fourth Amendment and must be treated as different in "a quantitative and qualitative sense" from other, non-digital personal items.
"Modern cell phones are not just another technological convenience," Roberts wrote. "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."
In a pair of related cases before the Court, one involving a smartphone and another a flip phone, state prosecutors and the Justice Department had argued that police need to be able to search cell phones and potentially other personal electronic devices to obtain the evidence needed to thwart criminal plots and catch suspects. But a wide swath of privacy advocates pushed back, saying that the vast amount of content typically stored on a person's phone could, if searched without a warrant, represent a sizable, intrusive breach into one's private life.
The Court did note that some case-by-case exceptions to the warrant requirement may apply, such as during "exigent" or pressing circumstances wherein an arresting officer's safety is in jeopardy.
In a concurring opinion, conservative Justice Samuel Alito said the technological demands of today called for "a new balancing of law enforcement and privacy interests." But Alito added that he would prefer legislatures were given more authority in creating rules to limit the warrant requirement in special cases.
"We should not mechanically apply the rule used in the predigital era to the search of a cell phone," Alito wrote. "Many cell phones now in use are capable of storing and accessing a quantity of information, some highly personal, that no person would ever have had on his person in hard-copy form."
But the Court also recognized the potential for its ruling to hamper police activity. Foundational privacy rights, however, must remain paramount, the justices reasoned.
"It is true that this decision will have some impact on the ability of law enforcement to combat crime," states the Court's summary of the opinions. "But the Court's holding is not that the information on a cell phone is immune from search; it is that a warrant is generally required before a search."
The Fourth Amendment protects Americans from unreasonable searches, which typically extends to items considered personal property. But decades of jurisprudence have granted law-enforcement officials the narrow right to search a suspect and the area within his reach "from incident to arrest."
Those decades-old standards, however, were crafted long before cell phones became ubiquitous, or even existed at all, and were largely intended to prevent a suspect from destroying evidence or using a nearby weapon.
Privacy advocates quickly cheered the decision and said it represents a paradigm-shift in how privacy concerns are being considered in Washington.
"The debate on privacy is clearly changing in a dramatic fashion, and 2014 has shown that in a number of ways," said Harley Geiger, senior counsel for the Center for Democracy & Technology, noting the House's passage of a government-surveillance reform bill as a recent example. "The Supreme Court's opinion recognizes that ... the quality and quantity of digital information that we carry around with us is different than physical information, and is deserving of rules that recognize those differences."
Senate Judiciary Chairman Patrick Leahy also hailed the decision. In a statement, the Vermont Democrat called the ruling "a wake-up call that we need to update our laws to keep pace with technological advances" while noting the same warrant-first standard should additionally be applied to government searches of email communications, a cause he has championed with legislation that would update the Electronic Communications Privacy Act.
Before Tuesday's ruling, state and federal courts were fractured on when a warrant was needed to rummage through a suspect's cell phone "from incident to arrest" and what contents should be allowable or off limits for authorities to search.
But in back-to-back oral arguments on a pair of related cases the Court heard in April, justices appeared torn on whether to draw a line on warrantless searches, and expressed frustration at the challenges of determining where that line should be in the ever-changing technological landscape.
Liberal Justice Elena Kagan most vocally raised privacy concerns during arguments, noting that police could arrest someone for driving without a seat belt and then proceed to look through the entire contents of that suspect's phone.
The two cases before the Court were joined into one decision. Riley v. California asked the Court to consider whether state police erred in 2009 when searching a San Diego man's smartphone twice — once at the scene of the arrest and again at the police precinct — before obtaining a warrant. Its companion case, U.S. v. Wurie, concerned a 2007 arrest of a suspected drug dealer in Boston who, upon arrest, had his flip phone seized and his call history promptly searched by authorities.