It’s been nearly a year since the U.S. Supreme Court ruled in Carpenter v. U.S, establishing murky rules to govern law enforcement access to the cell-site records that map the movements of anyone who carries a cellphone.

To Orin Kerr, a professor at USC Gould School of Law, the decision signals a new era in Fourth Amendment jurisprudence. We caught up with Kerr by email to ask about the pressures that digital technology places on the Fourth Amendment and where things go next.