Photo: Joe Ravi via Wikimedia Commons Nathan Wessler

This week on Law.com's Unprecedented podcast we talk with Nathan Wessler, a staff attorney with the ACLU's Speech, Privacy, and Technology Project. Wessler will be arguing against the Department of Justice on Wednesday at the U.S. Supreme Court in Carpenter v. U.S. The case centers on whether the government, in conducting criminal investigations, should need a warrant to obtain a suspect's cell-site location data covering long periods of time.

Wessler explains the ACLU's argument that the “third-party doctrine” doesn't apply, the role of the Stored Communications Act in the case, and what he sees as at stake for both companies and individuals. “Our primary argument to the court in this case is that nobody has ever expected that police would have access to this kind of historical map of everywhere someone's gone over days and weeks and months, and that the Fourth Amendment should have something to say about that,” Wessler says.

Listen to the full podcast online below, or on your iOS or Android device.