The Supreme Court will hear arguments on Tuesday in a case that could have broad implications for how modern surveillance technology is used to track criminals. The question at stake in The United States v. Antoine Jones is whether Fourth Amendment protections from “unreasonable searches and seizures” extends to GPS tracking and where the boundaries between public and private space lies in an era when many people are increasingly trackable through smart phones and other digital devices. Jeffrey Rosen, professor at George Washington University Law School, explains more about this unusual case.