Over the last 40 years, the US penal system has grown at an unprecedented rate—five times larger than in the past and grossly out of scale with the rest of the world. In The Punishment Imperative, eminent criminologists Todd R. Clear and Natasha A. Frost argue that America’s move to mass incarceration from the 1960s to the early 2000s was more than just a response to crime or a collection of policies adopted in isolation; it was a grand social experiment. Tracing a wide array...