In The Migrant's Jail, Dr. Nofil examines how a century of political, ideological, and economic exchange between the U.S. immigration bureaucracy and the criminal justice system gave rise to the world's largest system of migrant incarceration. Migrant detention is not simply an outgrowth of mass incarceration; rather, it has propelled carceral state-building and fostered intergovernmental policing efforts since the turn of the twentieth century.