The Fourth Amendment is the part of the Bill of Rights that prohibits "unreasonable searches and seizures." But — what's unreasonable? That question has fueled a century's worth of court rulings that have dramatically expanded the power of individual police officers in the U.S. Today on the show, how an amendment that was supposed to limit government power has ended up enabling it.

Guests:

Sarah Seo, professor of law at Columbia University, and author of Policing the Open Road: How Cars Transformed American Freedom.

Paul Butler, professor of law at Georgetown University and author of Chokehold: Policing Black Men.

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