National Crime Statistics Exchange (NCS-X)

Until January 1, 2021, the United States’ primary measure of crime known to law enforcement was monthly counts of ten offense categories—murder and nonnegligent manslaughter, rape, robbery, aggravated assault, burglary, larceny-theft, motor vehicle theft, arson, human trafficking-involuntary servitude, and human trafficking-commercial sex acts—based on the most serious offense reported for each crime incident. NIBRS was implemented in the late 1980s to improve the overall quality of crime data collected by law enforcement by capturing details on each single crime incident—and on separate offenses within the same incident—including information on victims, known offenders, relationship between victims and offenders, arrestees, and property, weapons, and/or drugs involved in crimes.

When NCS-X was designed in 2010, only about 25% of the nation’s roughly 18,000 law enforcement agencies contributed data to NIBRS. While the data collected through NIBRS was ideal for the NCS-X, agency participation rates did not meet minimum requirements for quantifying crime at the national-level. BJS determined it could produce national estimates of NIBRS data by enrolling a scientifically selected sample of 400 law enforcement agencies to submit data in addition to the agencies already participating in NIBRS.

In 2013, BJS and the FBI partnered on NCS-X and began working to expand NIBRS coverage through funding, training, and technical assistance to law enforcement agencies. The partnership leveraged the FBI’s existing NIBRS program infrastructure, allowing the two agencies to, (1) promote NIBRS data collection among the state Uniform Crime Reporting (UCR) programs, and (2) recruit the 400 NCS-X law enforcement agencies and support their transition to NIBRS.

State-Level Expansion of NIBRS

NCS-X funding and assistance were provided to two types of state entities--state UCR Programs and State Administering Agencies (SAA). In order to expand NIBRS reporting nationally, the NCS-X worked with state UCR Programs to ensure they were “NIBRS certified,” meaning the program demonstrated it was capable of collecting and processing NIBRS-compliant data from state and local law enforcement agencies and could transmit those data to the FBI. State-level NCS-X funding served two general purposes, to (1) help state UCR Programs upgrade or procure NIBRS-compliant data repositories and other software, hardware, or equipment necessary for improved data automation and transmission, and (2) expand incident-based reporting within the state by partnering with SAAs to administer subawards to state and local agencies selected into the NCS-X sample of 400.

As of April, 2022, all state UCR Programs were certified by the FBI to collect and submit NIBRS data. As of February, 2022, 11,525 law enforcement agencies were reporting to NIBRS, comprising 61.2 percent of all crime-reporting law enforcement agencies covering 64.5 percent of the U.S. population.

Local Agency Recruitment and Transition to NIBRS

Members of the NCS-X Technical Assistance and Implementation Team (NCS-X Team) worked directly with NCS-X selected agencies to identify gaps in their ability to report incident-based data. As part of recruitment activities, the NCS-X Team conducted Readiness Assessments to identify transition needs and associated costs to successfully collect and report compliant incident-based data. Funding was provided to improve data automation and reporting, with most eligible agencies receiving funds to obtain a NIBRS-compliant records management system (RMS) or other software, hardware, or equipment necessary to report to NIBRS. The NCS-X Team regularly met with award recipients to offer project guidance and technical assistance.

The transition to NIBRS means that statistics on crime reported by law enforcement will be based solely on data submitted to NIBRS. To generate national estimates of crime based on NIBRS data, BJS, in partnership with the FBI and with statistical and technical support from RTI International, established a new set of statistical procedures to estimate crime, based on data provided by NIBRS-contributing agencies.

The success of NCS-X, coupled with a broader reliance on data-driven insights by law enforcement, is reflected in the overall NIBRS coverage across the U.S., which has increased each year, as more law enforcement agencies submit data to the system. For the 2021 data year, 11,818 of the 18,924 law enforcement agencies in the United States submitted at least 1 month of data to NIBRS, representing approximately 65% of the U.S. population. For the 2022 data year, 13,624 of the 18,930 agencies in the United States submitted at least 1 month of data to NIBRS, representing approximately 79% of the U.S. population. For the 2023 data year, 14,039 of the 19,196 agencies in the United States submitted at least 1 month of data to NIBRS, representing about 83% of the U.S. population.

The NIBRS Estimation Project page contains additional information about the collaboration between BJS and the FBI and links to resources about the project.

More than 18,000 law enforcement agencies collect and report crime data to the Uniform Crime Reporting (UCR) program, either through the Summary Reporting System (SRS) or NIBRS. The NCS-X sample was drawn from law enforcement agencies that had reported crime data to the SRS in 2011. SRS data contributors were stratified into 11 strata or categories by agency type and total number of sworn personnel. 

All of the nation’s law enforcement agencies employing 750 or more sworn personnel that were not already reporting to NIBRS were included in the NCS-X sample. Agencies assigned to the remaining strata were selected at random, with varying probability, to ensure the number of agencies sampled within each stratum was proportional to the number of agencies in each stratum. 

• NCS-X Sample of 400 Law Enforcement Agencies

The NCS-X Team is led by BJS and supported by the FBI Criminal Justice Information Division (CJIS), RTI International, the Integrated Justice Information Systems (IJIS), the National Consortium for Justice Information and Statistics (SEARCH), the International Association of Chiefs of Police (IACP), the Police Executive Research Forum (PERF), and the Association of State Uniform Crime Reporting Programs (ASUCRP).

The NCS-X Team assists participating agencies by coordinating information across state and local law enforcement agencies, state UCR Programs, the law enforcement technology industry, and other key stakeholders to provide guidance to transitioning agencies and promote efficient and economical practices.

The NCS-X Team also produced resource and other materials for state UCR Programs and for state and local law enforcement agencies, to support the expansion of NIBRS reporting.

Planning a statewide transition to incident-based reporting:

• State IBR Playbook: A Guide to Implementing a Statewide Incident-Based Crime Reporting System
• IBR Implementation Planning
• Estimating Costs for Transitioning to NIBRS: Guidance for State UCR Programs
• NIBRS Readiness Assessment Guide: Implementing an Incident-Based Crime Reporting System

NIBRS data assessment tools:

• NIBRS Precertification Tool: tests agency generated data files against NIBRS data edit and validation rules. The free software provides formatted output of errors, in order for agencies to correct their data submissions prior to testing for IBR certification.
• NIBRS to SRS Conversion Tool: allows agencies to compare incident-based crime data to historical summary data by exercising UCR Summary Reporting System (SRS) reporting rules to collapse NIBRS-compliant data.

Planning an agency transition to incident-based reporting:

• Local IBR Playbook: A Guide to Implementing an Incident-Based Reporting System
• Estimating Costs for Transitioning to NIBRS: Guidance for Local Law Enforcement Agencies
• NCS-X NIBRS Readiness Assessment for Agencies with a Commercial Off the Shelf (COTS) RMS
• NCS-X NIBRS Readiness Assessment Form for Agencies with an In-House/Custom RMS
• NIBRS -- Acquiring Incident-Based Reporting (IBR) Software and Services, includes:
  • Key Topics for Law Enforcement to Consider
  • Model Statement of Work
• Customizable Power Point Presentation: Moving from Summary to Incident-Based Reporting

NIBRS data assessment tools:

• NIBRS Precertification Tool: tests agency generated data files against NIBRS data edit and validation rules. The free software provides formatted output of errors, in order for agencies to correct their data submissions prior to testing for IBR certification.
• NIBRS to SRS Conversion Tool: allows agencies to compare incident-based crime data to historical summary data by exercising UCR Summary Reporting System (SRS) reporting rules to collapse NIBRS-compliant data.

• The Nation's Move to NIBRS: Formulating the Future of Crime Data in Policing - Workshop Proceedings (2021).
• NIBRS Transition Summary: Montgomery County, MD, Police Department
• NIBRS Transition Summary: Fort Worth, TX, Police Department
• Will NIBRS Reporting Increase Crime Statistics? Tips for Responding to Questions (2020)
• Multiple Offense Incidents in the National Incident-Based Reporting System (2019)
• Tech Talk: Got NIBRS? Finding Efficiencies and Funding to Support Your Agency's Transition (2018)
• Research in Brief: Leveraging NIBRS to Better Understand Sexual Violence (2018)
• The Future of Crime Data: The Case for the National Incident-Based Reporting System (NIBRS) as a Primary Data Source for Policy Evaluation and Crime Analysis (2017)