On December 7, Attorney General Loretta Lynch announced a federal investigation of the Chicago police department. Recent history shows that the Obama Department of Justice cannot be counted on to perform a competent investigation, but at least this particular inquiry is not without cause. The city has earned the nickname “Chiraq,” because by international standards, certain Chicago neighborhoods have some of the highest murder rates anywhere in the world. Even as the city has become an abattoir, police have been routinely abusive—a series of troubling investigations suggests the police were operating a “black site” out of an off-the-books warehouse where cops were holding and interrogating suspects without due process. Such extraordinary tactics are intolerable in principle, and the fact that they generated no notable decline in crime suggests they were also bad in practice.