Historical statistics on prisoners in the U.S. are far inferior to those available for England and Wales. Yearly counts of prisoners in all types of penal institutions in England and Wales are available from 1836. In the U.S., such statistics are available only from 1983.

Penal systems across the U.S. have considerable institutional diversity. Local jails historically have been distinguished in the U.S. from prisons run by state governments. Municipal, county, regional, state, and federal government organizations have all operated penal institutions called penitentiaries, prisons, workhouses, houses of correction, correctional institutions, jails, prison farms, prison camps, chain gangs, and road gangs. Vermont, Rhode Island, Connecticut, Delaware, Alaska, Hawaii, and the District of Columbia combine the operation of local jails with state prisons in their criminal justice systems.

Distinct U.S. federal prisons arose long after state and local prisons. In the nineteenth century, federal prisoners (who were few) probably were held in the Albany State Penitentiary in New York State. In 1895, federal prison at Leavenworth, Kansas, began operation, and in 1902, a federal prison in Atlanta, Georgia. The U.S. Federal Bureau of Prisons was established in 1930.

Distinguishing state prisons and reformatories from other penal institutions can be difficult. In states that combined operations of prisons with jails, the institutional distinction between state prisons and local prisons (jails) isn’t meaningful. While houses of correction typically were local institutions, some, such as the Detroit House of Correction, were state institutions. The term inmates is sometimes used for persons held in jails, or for all persons held in prisons and jails. In this work, prisoners and inmates represent synonyms for persons confined by the criminal justice system. The terms “prisoner” and “in prison”, where not otherwise qualified, do not imply any distinction among types of penal institutions. More specific terms are used as direct references to the same categories used in the data source under consideration.

Counts of persons (prisoners) present in government-run penal institutions indicate persons absent in punishment from ordinary life. These counts are not the same as the numbers of persons committed to prison during a given period. Ideally the count of prisoners present would be the average daily number present during the year, but for U.S. prisoner statistics only counts on a given day are typically available. Prisoner counts in this work exclude, where possible, juveniles in special institutions for juveniles (juvenile reformatories), persons in military prisons, and persons in insane asylums or insane hospitals. The counts include unsentenced prisoners and persons in prison for nonpayment of fine and for debt.

The most comprehensive, most consistent long-run series for U.S. prisoner populations are decennial prisoner statistics from the U.S. national censuses. These statistics first become available in 1850. Annual national statistics for prisoners in federal and state prisons and reformatories are available from 1925. Using additional U.S. Bureau of Justice Statistics (BJS) data on jail inmate populations, available from 1970, alternate estimates of total prisoners in the U.S. can be constructed. After 1980, these estimates are within a few percentage points of the census prisoner counts. Earlier BJS totals differ more from census figures primarily because of differences in counts of prisoners in jails. The census data on prisoners comes from a well-bounded bureaucracy dedicated to a general program of enumeration that has been administered throughout U.S. history. That bureaucratic structure is more likely to produce consistent, correct indicators over the long run.

Under a grant from BJS to Westat, Inc., Margaret Werner Cahalan, with the assistance of Lee Anne Parsons, produced the 1986 BJS report, Historical Corrections Statistics in the United States, 1850 – 1984. The statistics shared here were compiled with the benefit of that BJS reports. The statistics shared here include additional work to estimate consistent national prisoner totals, and more effort to distinguish prisoners by sex.

Available online prisoner statistics workbooks:

• unified statistics on U.S. prison and jail populations from 1850 to 2010
• U.S. prisoner statistics for the nineteenth century
• U.S. prisoner statistics from 1900 onwards
• U.S. federal and state prisoner populations by state and sex from 1880
• U.S. federal and state prisoners by prison facility c. 1940: matching BJS and Census data
• federal and state prisoners by individual prisons, 1868-1938