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Search Warrant Required for CSLI


Each time a phone connects to a cell site, it generates a time-stamped record known as cell-site location information (“CSLI”). Wireless carriers collect and store this information for their own business purposes. CSLI can pinpoint a cell phone’s location, within a certain range, for as far back as five years, which is the standard retention policy for most wireless carriers.

In Carpenter v. United States (2018), the Supreme Court of the United States was presented with the question of whether the acquisition of an individual’s CSLI by police was a “search” and afforded protection under the Fourth Amendment.

In a 5-4 decision, the Court found that it was a search and, as a result, the police must generally obtain a warrant, supported by probable cause, before obtaining CSLI records.

This decision comes off the heels of the Court’s recognition that police must have a warrant prior to searching an individual’s cell phone, which the Court found “hold for many American’s the privacies of life.” For a prior blog on that decision, click here.

The Moore Law Firm has been involved in several serious cases over the years involving the use of CSLI. Our attorneys are familiar with the expert witnesses in this field and are prepared to address the intricate issues involved with CSLI in litigation.