Orin Kerr writes:
On October 2, the Fifth Circuit will hold oral argument in case No. 11–20884, In Re Applications of the United States for Historical Cell-Site Data. In this case, the United States applied for a court order under the Stored Communications Act to compel cell phone providers to disclose location information about particular phones suspected in criminal investigations. The magistrate judge denied the applications on the ground that he expected that the orders would be executed in ways that will violate the Fourth Amendment. The government has appealed the denial of the orders, arguing that the orders will be executed in ways that comply with the Fourth Amendment. Although the government is the only party to the litigation, several amici have chimed in on the merits to defend the denial of the applications on the ground that the magistrate judge was right to fear that the orders would be implemented in ways that would violate the Fourth Amendment. You can read the various briefs here, and the government’s reply to the amicus briefs is here.
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