Information about crime comes from two primary sources: survey responses from victims about crimes they experienced and administrative data from law enforcement agencies about crimes reported to them. Victim survey responses capture information on crimes reported to the police, as well as those crimes that were not reported. Crime data from law enforcement agencies reflect those crimes reported to and recorded by police.
The Nation's Two Crime Measures
Department of Justice agencies collect both survey and administrative data on crime.
- BJS's National Crime Victimization Survey (NCVS) captures incident-level data on reported and unreported crime from the victim's perspective
- FBI's Uniform Crime Reporting (UCR) Program Summary Reporting System (SRS) collects summary-based counts of crime reported by law enforcement
Similar to many other indicators used to assess conditions in the United States, these two indicators of crime complement each other to produce a more comprehensive portrait of the nation's crime problem.
Some of the differences between SRS and NCVS are—
|Summary Reporting System||National Crime Victimization Survey|
National and state estimates, local agency reports
Data can be aggregated to county-level and federal judicial district
|Collection method||Reports by law enforcement to the FBI on a monthly basis||Survey data obtained from a nationally representative sample of about 240,000 interviews, which involves 160,000 unique persons in about 95,000 households.|
|Measures||Aggregate counts of 10 offense types reported by law enforcement||Reported and unreported crime; details about the crimes, victims, and offenders|
For more information about the UCR and the NCVS, see The Nation's Two Crime Measures.
On January 1, 2021, the SRS was retired, and the FBI UCR Program transitioned to incident-based submissions of reported crime data to the National Incident-Based Reporting System (NIBRS). For more information on the transition to NIBRS, see the National Crime Statistics Exchange (NCS-X) program page.
There are two national crime series which have data on crime rates and trends. The National Crime Victimization Survey (NCVS) is based upon a sample of households and includes both crimes that are reported to police and those that are not reported. The Uniform Crime Reports (UCR) is based upon local police reports which are compiled by the FBI. See (link) for a more detailed explanation of each data set. The two data series complement each other and both are “right” in terms of measuring what they are designed to measure. Please see the report, The Nation’s Two Crime Measures (NCJ 246832, BJS web), for more information.
Number of victimizations per 1,000 persons or households in a given population that occurred during the year.
NIBRS stands for National Incident-Based Reporting System. Unlike the FBI's Uniform Crime Reporting (UCR) Program, which only collects data on the most serious offense that occurs during a criminal incident, NIBRS collects data on each reported offense occurring during criminal incident. You can learn more about NIBRS in the NIBRS Edition of the FBI's CJIS newsletter.