Originally, the UCR Program was designed as a summary system to collect only the most serious offenses within an incident.  However, the FBI UCR Program began using incident-based reporting (i.e., NIBRS) in 1989 to capture all offenses within an incident – up to ten crime occurrences.  It retired the summary system on January 1, 2021, and now only accepts NIBRS data.  Through NIBRS, law enforcement agencies report data on each offense and arrest within 28 offense categories made up of 71 specific crimes called Group A offenses. For each of the Group A offenses coming to their attention, the law enforcement agency collects administrative, offense, property, victim, offender, and arrestee information. In addition to the Group A offenses, there are 10 Group B offense categories for which only arrest data are reported. (From the 2021.1 National Incident-Based Reporting System User Manual)

In addition to expanding the reported offenses, other data is collected in NIBRS which was unavailable in summary UCR. The additional data includes weapons or force used; injuries received; relationships between victims and offenders; crime locations; victim, offender and arrestee age, sex and race; victim and arrestee residency and ethnicity; victim type (such as individual, business, government, religious and financial institutions); use of alcohol, drugs and/or computers by offenders; and the circumstances of aggravated assaults and homicides. Specialized crime data can be generated from this data, such as crimes against the elderly, crimes against women, and domestic violence. Also, state and local agencies can add other data to address issues of importance to them for analysis.

NIBRS measurably strengthens the information arsenal of law enforcement in apprehending criminals and reducing crime. The common link of NIBRS provides a data backbone for data sharing in cross-jurisdictional crime-fighting efforts.

Since data collected by NIBRS are comprehensive, agencies that participate should have computerized data systems capable of processing NIBRS information. NIBRS was designed to be a byproduct of an existing automated law enforcement records system.

An indispensable tool in the war against crime is the ability to identify with precision when and where crime takes place, what form it takes, and the characteristics of its victims and perpetrators. NIBRS provides law enforcement with that tool because it is capable of producing more detailed, accurate, and meaningful data than produced by the traditional summary UCR Program.

Many individual law enforcement agencies have very sophisticated records systems capable of producing the full range of statistics on their own activities. NIBRS allows common denominator links among agencies. It provides law enforcement agencies with extensive, specific crime information concerning similar jurisdictions, allowing the identification of common crime problems or trends. Agencies can then work together to develop possible solutions or proactive strategies for addressing the issues. (From the 2021.1 National Incident-Based Reporting System User Manual)