; Census of Jails ;

Frequently Asked Questions

What is the Census of Jails (COJ)?

The Census of Jails (COJ), conducted by the Bureau of Justice Statistics (BJS), is a leading source of statistical information about jail facilities and inmate populations. This periodic survey, administered in 1970, 1972, 1978, 1983, 1988, 1993, 1999, 2005/2006, 2013, 2019, and 2024, captures data on inmate counts, population characteristics, admissions and releases, and facility attributes and programs. The COJ is the only national jail data collection that provides state-level and jail-level information, covering approximately 2,800 local jails nationwide, including city, county, regional, and private jails, as well as 12 Federal Bureau of Prisons detention facilities functioning as jails.

Who is conducting the COJ?

The COJ is funded and managed by the Bureau of Justice Statistics (BJS), a federal government agency under the U.S. Department of Justice and a principal agency of the U.S. Federal Statistical System. BJS's primary mandate is to collect criminal justice data and to disseminate information for statistical analysis. The COJ is BJS’s longest-running and most comprehensive national data collection effort focused on jails.

BJS has partnered with RTI International to act as the data collection agent for the COJ. RTI is a nonprofit research institute, headquartered in the Research Triangle Park in North Carolina, specializing in research and technical services. Since 2013, RTI has played a vital role as the data collection agent BJS’ jail collections.

Why is my agency invited to participate in the COJ?

The COJ aims to enumerate every county, municipal, regional, and private jails in the United States. All local or regional law enforcement agencies overseeing adult confinement facilities are encouraged to participate in the COJ (see "What types of facilities are included in the COJ?"). If your agency is new to BJS's jail surveys, please reach out to jailcensus@rti.org to determine if your agency is eligible for the COJ.

What types of facilities are included in the COJ?

The Census of Jails covers all adult confinement facilities administered by a local or regional law enforcement agency, which may occasionally house juveniles. These facilities typically have the authority to detain individuals beyond arraignment, often exceeding a 72-hour period. Jails receive individuals pending arraignment and hold them as they await trial, conviction, or sentencing. Additionally, jails hold sentenced inmates with a sentence of one year or less.

The census includes the following types of facilities—

  • city/county/regional jails and correctional centers
  • special jail facilities overseen by local or regional correctional authorities, such as rehabilitation centers, diversion centers, reception centers, reentry facilities, and work release centers
  • temporary holding or lockup facilities integrated into a local jail system
  • private facilities under contracts with local, regional, or federal correctional authorities.

The census excludes—

  • Juvenile detention facilities under the juvenile justice system
  • Lockup facilities that do not hold inmates beyond arraignment or for more than 72 hours (unless they are part of a larger, integrated local jail system).

Is participation in the COJ voluntary?

Participation in the COJ is voluntary, yet we highly encourage all jails to engage in this census. The data collected through the COJ are instrumental in shaping policies, enhancing services, and guiding decision-making concerning jail operations and inmate populations. Your participation offers jails invaluable insights into industry trends, facilitates benchmarking against peer institutions, and aids in identifying areas for improvement.

How long will it take to complete the survey?

About 2 hour and 30 minutes.

What questions are on the COJ?

The 2024 COJ included 24 questions on jail population, facilities, and programs, such as:

  • The number of persons held in your jail facilities on the last weekday in June, categorized by sex, age group, race/ethnicity, conviction status, offense severity, and other characteristics
  • Admissions, releases, and average daily population for the 12-month period ending June 30, 2024, categorized by sex
  • Jail functions, rated capacity, and the number of employees
  • Programs related to the screening and treatment of opioid use disorders and withdrawals.

The survey form is available for review here.

What is the reference date for the 2025 COJ?

Starting with the 2025 COJ, the reference date will be the last Monday in December. The reference date for the 2025 COJ will be December 29th, 2025. You will be asked about your jail’s confined population on that date. You will also be asked to provide information on admissions, releases, and average daily population for the 12-month period from January 1, 2025, to December 31, 2025.

What are my agency's username and password?

Your agency's username and password are provided in your invitation to participate in the COJ. If you have lost this information, please send your name and agency name to jailcensus@rti.org or call (866) 354-4992.

How secure are the COJ data?

As a federal statistical agency, Bureau of Justice Statistics’ (BJS) procedures for collecting, analyzing, publishing, and distributing data are subject to strict federal controls, ensuring the quality, security, and integrity of our nation's criminal justice statistics. BJS and its data collection agents may only use the data collected under its authority for research and statistical purposes. BJS's governing regulations and statutes include—

  • 42 USC § 3732 (BJS authorizing legislation)
  • 42 USC § 3735 (BJS use of data statute)
  • 42 USC § 3789g (BJS confidentiality of information statute)

For more information on the federal statutes, regulations, and other authorities that govern how BJS, BJS employees, and BJS data collection agents use, handle, and protect your information, see the BJS Data Protection Guidelines.

What is the Bureau of Justice Statistics (BJS)?

Bureau of Justice Statistics (BJS) is a federal government agency under the U.S. Department of Justice and a principal agency of the U.S. Federal Statistical System. BJS's principal function is to collect criminal justice data and to disseminate information for statistical purposes. The COJ is BJS’s longest-running and most comprehensive national data collection on jails.

What is RTI?

RTI International is a nonprofit research institute, headquartered in the Research Triangle Park in North Carolina, that provides research and technical services. RTI has been a key data collection agent for the Bureau of Justice Statistics’ jail collections since 2013. For more information about RTI, please visit http://www.rti.org.

What if I have other questions?

If you have questions about providing your data to the COJ, please contact the RTI data collection team at (866) 354-4992 or jailcensus@rti.org. If you have additional questions about the COJ, please contact the BJS program manager, Zhen Zeng, at Zhen.Zeng@usdoj.gov.