A federal appeals court on Wednesday rejected the Obama administration's contention that the government is never required to get a court warrant to obtain cell-site information that mobile-phone carriers retain on their customers.

The decision by the 3rd U.S. Circuit Court of Appeals is one in a string of court decisions boosting Americans' privacy (.pdf) in the digital age – rulings the government fought against. The most significant and recent decision came Tuesday, when a different federal appeals court said for the first time the government must obtain a court warrant for an internet service provider to grant the authorities access to a suspect's e-mail.

The case that concluded Wednesday concerns historical cell-site location information, which carriers usually retain for about 18 months. The data identifies the cell tower the customer was connected to at the beginning of a call and at the end of the call – and is often used in criminal prosecutions and investigations.

"Prosecutors across the country use the statute in criminal investigations to obtain a wide range of evidence," (.pdf) the administration told the Philadelphia-based 3rd Circuit.

The Stored Communications Act, the appeals court ruled in September, granted judges the discretion to require a warrant under the Fourth Amendment for the government to obtain the cell-site information. It was the first appellate court to reach that conclusion, despite a handful of lower-court decisions freeing the government from that requirement.

The Obama administration urged the appellate court to reconsider its position, an offer the court declined Wednesday without commenting on the merits.

The administration has also asked the U.S. Court of Appeals for the District of Columbia Circuit to reverse its August ruling requiring court warrants to affix GPS devices to vehicles to track their every move. The administration said Americans should expect no privacy "in the totality of his or her movements in public places."

The appellate court's answer is pending.

Photo:Keithius/Flickr

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