Correction to This Article
This article incorrectly said that a federal court decision on the government's ability to obtain stored cellphone location data was the first federal district court ruling on the issue. It was the first federal district court ruling to hold that the government must obtain a warrant based on probable cause before seeking such information; two other district court rulings have found that the government may obtain the data on a standard lower than probable cause.

Judge Limits Searches Using Cellphone Data

By Ellen Nakashima
Washington Post Staff Writer
Friday, September 12, 2008

The government must obtain a warrant based on probable cause of criminal activity before directing a wireless provider to turn over records that show where customers used their cellphones, a federal judge ruled Wednesday, in the first opinion by a federal district court on the issue.

Judge Terrence F. McVerry of the Western District of Pennsylvania rejected the government's argument that historical cellphone tower location data did not require probable cause.

The ruling could begin to establish the standard for such requests, which industry lawyers say are routine as more people carry cellphones that reveal their locations. Around the country, magistrate judges, who handle matters such as search warrants, have expressed concern about the lack of guidance.

In this case, which involved a government investigation of a drug trafficker, the judge affirmed a February ruling by U.S. Magistrate Judge Lisa Pupo Lenihan that whether the data sought was historical or real-time, it required a warrant.

"This is a great ruling for location privacy and for people who think the government should have probable cause before they track you," said Jennifer Granick, an attorney with the Electronic Frontier Foundation, which filed a friend-of-the-court brief in the case.

But Orin Kerr, a constitutional law expert at George Washington University, said the decision was "very likely wrong" and faces "an uphill battle on appeal."

The government is "considering options" on an appeal, Justice spokesman Dean Boyd said.

At issue was a government request for an order directing Sprint Spectrum to disclose historical cellphone data that included cell tower location information as well as call times and durations.

Lenihan said the information sought, which she said could identify a subject's location to within about 200 feet, was "extraordinarily personal and potentially sensitive . . . (and) particularly vulnerable to abuse."

The government argued that cell site historical records are no different from routine transactional records and as such are not "tracking devices" that require a warrant.

"For instance, records of past credit card transactions will often serve to place a person at a given location at a specific time, yet under established Fourth Amendment law they enjoy no Fourth Amendment protection," U.S. Attorney Mary Beth Buchanan said in a brief asking the district court to review Lenihan's ruling.

She argued that historical cell-site records reveal location only to within a few hundred yards, not feet, and are "much too imprecise" to tell whether calls have been made from a "constitutionally protected space, let alone to reveal facts about the interiors of private homes or other protected areas."

To obtain such orders, the government said, the correct standard is a showing of "specific and articulable facts" that the information is "relevant" to a criminal investigation. A "majority of federal districts" grant orders based on that standard, Boyd said.

But Catherine Crump, a lawyer with the American Civil Liberties Union, said the government's position on historical data was flawed. "People place a certain privacy value on their movements," she said. "Whether it's their movements yesterday or their movements today, it's the same."

Said Granick: "Most people don't think that somebody could go back in time and find out where I was or who I was talking to or who was nearby at that same time. This is sensitive information, and there should be good reason before the government gets it."

For more precise cellphone location, such as by Global Positioning System technology in phones, Justice Department attorneys say access requires a warrant.

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