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Census of Jails (COJ)

Data Collection Status
Active
Frequency
Periodically from 1970 to 2024, and annually beginning in 2024
Data Experts
Zhen Zeng, PhD, BJS Statistician
Todd D. Minton, BJS Statistician
Collection Period

1970, 1972, 1978, 1983, 1988, 1993, 1999, 2005/2006, 2013, 2019

Description

The Census of Jails (COJ) is the Bureau of Justice Statistics’ primary data collection on local jails. From 1970 to 2024, the COJ was conducted every 5 to 6 years, collecting data from about 2,900 local jails and federal detention facilities to produce state- and national-level statistics on jail populations and facilities. The COJ provides detailed information on inmate characteristics—including sex, race, Hispanic origin, citizenship, juvenile status, conviction status, and holds for other jurisdictions—as well as counts of admissions, releases, and average daily population. It also collects data on facility characteristics such as capacity, staffing, and programs, with certain topics rotated across years to reduce burden. As the only collection that enumerates all local jails, the COJ serves as the sampling frame for BJS’s other jail surveys, including the Annual Survey of Jails, the Survey of Inmates in Local Jails, and the National Inmate Survey. Beginning in 2024, the COJ transitioned to an annual collection to provide more timely state-level statistics.

Date Created: May 20, 2009