Police need a warrant to track the cellphones of criminal suspects, a federal appeals court ruled Wednesday in a development that could help resolve a privacy issue that has split judges nationwide.

The 11th U.S. Circuit Court of Appeals in Atlanta held that the government violated the privacy rights of Quartavius Davis, who was convicted of robbing seven stores in 2010—including a Little Caesar's restaurant, a Walgreens drugstore and a jewelry shop—and sentenced to roughly 162 years in prison.

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