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SCOTUS Decision in Cell Phone Tracking Case

Today the Supreme Court of the United States issued a decision , Carpenter v. United States, reversing the Sixth Circuit's affirmance of the Eastern District of Michigan's denial of a defendant's motion to suppress CSLI data (cell-site location information). The Litigation Support Tip of the Night for December 6, 2017 discussed the oral argument in this case. CSLI data is generated each time a cell phone connects to a cell phone tower. The FBI obtained court orders under the Stored Communications Act of to obtain the cell phone records of suspects in a robbery case. The CSLI of the petitioner in this case, Timothy Carpenter, showed that he was nearby the location of four robberies at the time the robberies occurred. (Carpenter's phone generated CSLI showing his location on average more than 100 times a day).

The Supreme Court held that the Government's acquisition of the CSLI records constituted a Fourth Amendment search. Personal location information concerns both an individual's expectation of privacy with respect to his physical location, and his expectation of privacy in information given to third parties. The Court distinguished CSLI data from 'pen register' phone call data and banking records which the Supreme Court previously held to not be covered by the Fourth Amendment in Smith v. Maryland, 442 U.S. 735 (1979), and United States v. Miller. 425 U.S. 435 (1976) respectively. CSLI data is not voluntarily shared in the same way dialed phone numbers or business records are. "[A] cell phone logs a cell-site record by dint of its operation,without any affirmative act on the part of the user beyond powering up." Carpenter v. United Sates, 585 U. S. ____, slip op. at 17 (June 22, 2018).

The Court found that CSLI data raises greater privacy concerns than GPS data, because it allows authorities to track a person's movements over time.

The Court chose not to call into question other business records that might indicate a person's location. It also noted that exigent circumstances might justify a warrantless search of CSLI.

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