Today's guest is Dr. Matthew Guariglia, a senior policy analyst for the Electronic Frontier Foundation and author of the new book, Police and the Empire City: Race and the Origins of Modern Policing in New York, just out from Duke University Press. Guariglia says we're really living in a world of police surveillance built in the early 20th century, even as police departments wield powers that only a few years ago we thought might only be in the hands of federal intelligence agencies.