In Major Privacy Win, Supreme Court Rules Police Need Warrant To Track Your Cellphone The sharply divided justices ruled that police need a search warrant to obtain cellphone location data.


In Major Privacy Win, Supreme Court Rules Police Need Warrant To Track Your Cellphone

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In a landmark decision, the U.S. Supreme Court ruled today that police must obtain a search warrant in order to gain access to an individual's cellphone location information. The 5 to 4 decision imposes new limits on law enforcement's ability to get at the increasing amount of data that private companies amass in the modern technological age. NPR legal affairs correspondent Nina Totenberg reports.

NINA TOTENBERG, BYLINE: Customers' cellphone location information is routinely kept by cellphone providers to help them improve service. And until today, under the Supreme Court's prior rulings, the prevailing legal theory was that if an individual voluntarily shares his information with a third party by signing up for service, for instance, police do not need a search warrant to get that information from the service provider. Today, the Supreme Court blew a hole in that theory.

Writing for the court majority, Chief Justice John Roberts said that cellphone location information is the perfect tool for government surveillance, analogous to an electronic monitoring bracelet. The writers of the Constitution, he said, would certainly have understood that an individual has a privacy interest in day-to-day, hour-to-hour and even minute-to-minute records of his whereabouts, a privacy interest that requires the government to get a search warrant before gaining access to that information.

The case before the court was brought by Timothy Carpenter, prosecuted as a ringleader in a series of armed robberies in Michigan and Ohio. Cell tower location information showing he was at the robbery sites was used as damning evidence at his trial. Carpenter appealed his conviction, contending that police invaded his privacy without getting a search warrant first. Today, the Supreme Court agreed, declaring that the routine court order that police obtained in Carpenter's case only required a showing that police were seeking relevant information, whereas a search warrant requires that police meet a far higher standard.

ORIN KERR: Big Brother is coming, and we need to stop it. That seems to be the big takeaway from the opinion.

TOTENBERG: Fourth Amendment scholar Orin Kerr of the University of Southern California.

KERR: It almost reflects an anxiety about technology thwarting privacy. If we don't stop the government here, what will they be able to do?

TOTENBERG: Columbia law professor Jameel Jaffer.

JAMEEL JAFFER: This is a landmark privacy case. But it's also a very significant case for First Amendment freedoms - that is, for the freedoms of speech and the press and association. A government that can track your every movement without a warrant is a government that can freely monitor activists' political associations or monitor government employees' contacts with the press.

TOTENBERG: But Jaffer concedes that today's decision poses practical problems and leaves open important questions. Chief Justice Roberts cast the decision as a narrow one. It does not disturb the routine use of subpoenas to obtain financial, bank and other business records, he said, nor does it prevent police from obtaining cell location records without a warrant in emergency circumstances like a fleeing suspect, a kidnapping or threats of imminent danger.

Moreover, he said, the decision does not call into question the use of security cameras and other techniques, and it does not consider other collection techniques involving foreign affairs and national security. What it does do, he said, is to ensure that the progress of science does not erode the Fourth Amendment guarantee of privacy.

Roberts, a conservative, was joined by the court's four liberal justices. The court's other four conservatives dissented loudly, each writing separately to indicate his strong disagreement. While each had a different approach, they all said today's decision would lead to confusion, litigation and problems for law enforcement. Ed McAndrew, a former federal prosecutor, agrees. He notes that cell location information is often gathered at the early stages of an investigation when there isn't enough information for a search warrant. The same is true in terrorism and national security investigations.

ED MCANDREW: And the national security context is only going to be different if we're dealing with foreign nationals. If we're dealing with American citizens, the Fourth Amendment principle's going to apply.

TOTENBERG: Justice Stephen Breyer, who joined today's majority opinion, may have foreseen some of these problems at oral argument.


STEPHEN BREYER: This is an open box. We know not where we go.

TOTENBERG: Nina Totenberg, NPR News, Washington.

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