Census of Jails (COJ)

The Census of Jails (COJ) collects data on jail facilities and the inmate populations they supervise. Administered to nearly 3,200 local jails (city, county, regional, and private) nationwide and the 12 Federal Bureau of Prisons (BOP) detention facilities that function as jails, the COJ provides state and national estimates on the number of inmates confined in jails, characteristics of the jail population, counts of admissions and releases, and jail facility characteristics. The COJ includes all locally operated jails in 45 states and the District of Columbia, and 15 locally operated jails in Alaska. It excludes temporary holding facilities and state-operated facilities in Connecticut, Delaware, Hawaii, Rhode Island, and Vermont. The 2019 COJ collected data on facility characteristics and programs, including rated and design capacity, staffing, and opioid testing and treatment protocols. It also collected data necessary for producing estimates on local jail populations, including one-day custody counts by sex, conviction status, severity of offense (felony and misdemeanor), counts of U.S. citizens and non-U.S. citizens, juvenile counts, and holds for U.S. Immigration and Customs Enforcement (ICE) and other state and federal authorities, average daily population, admissions, releases, and turnover rates.