Statistics regarding prisons are taken from various reports of the Bureau of Justice Statistics of the US Department of Justice.

With 50 states following 50 different patterns, there is much heterogeneity in the actual way these eras played out “on the ground.” But these dates and dynamics are a good representation of national trends.

These eras are adapted from Lynch and Sabol 2000. Prison Use and Social Control, In Policies, Processes, and Decisions of the Criminal Justice System: Criminal Justice 2000, Volume 3. Washington, DC: National Institute of Justice.