For much of America’s history, we simply did not lock people up for migrating here. Yet over the last thirty years, the federal and state governments have increasingly tapped their powers to incarcerate people accused of violating immigration laws. As a result, roughly 400,000 people a year now spend some time locked up pending civil or criminal immigration proceedings.

César Cuauhtémoc García Hernández‘s new book takes a hard look at the immigration prison system’s origins, how it currently operates, and why. It tackles the outsized presence of private prisons and how those on the political right continue, disingenuously, to link immigration imprisonment with national security risks and threats to the rule of law.

César Cuauhtémoc García Hernández is a professor of law at the University of Denver and an immigration lawyer. He runs the blog Crimmigration.com.