13th explores the intersection of race, justice, and mass incarceration in the United States, as titled after the Thirteenth Amendment to the United States Constitution, adopted in 1865, which purported to abolish slavery throughout the United States and end involuntary servitude except as a punishment for conviction of a crime. The film contends that slavery has been perpetuated since the end of the American Civil War through criminalising behaviour and enabling police to arrest poor enslaved people and force them to work for the state under convict leasing; suppression of African Americans by disenfranchisement, lynchings and Jim Crow; politicians declaring a war on drugs that weighs more heavily on minority communities and, by the late 20th century, mass incarceration of people of colour in the United States. 13th examines the prison-industrial complex and the emerging detention-industrial complex, discussing how much money is being made by corporations from mass incarcerations.