The Uniform Crime Reporting Program Handbook (Federal Bureau of Investigation, 2004:3) describes the origin of a new, more detailed format for the UCR as follows:
By the 1980s, law enforcement was calling for a complete overhaul and modernization of the UCR Program. At a conference on the future of UCR, which was held in Elkridge, Maryland, in 1984, participants began developing a national data collection system that would gather information about each crime incident. By the end of the decade, the National Incident-Based Reporting System (NIBRS) was operational. NIBRS collects data on each incident and arrest within 22 offense categories made up of 46 specific crimes called Group A offenses. For each incident known to police within these categories, law enforcement collects administrative, offense, victim, property, offender, and arrestee information. In addition to the Group A offenses, there are 11 Group B offenses for which only arrest data are collected. The intent of NIBRS is to take advantage of available crime data maintained in modern law enforcement records systems. Providing considerably more detail, NIBRS yields richer and more meaningful data than those produced by the traditional summary UCR system. The conference attendees recommended that the implementation of national incident-based reporting proceed at a pace commensurate with the resources and limitations of contributing law enforcement agencies.
The NIBRS incident report is quite intricate and allows for great flexibility in the coding of individual events: spanning 46 offense categories, each incident report can include up to 10 offenses, 3 weapons, 10 relationships to victim, and 2 circumstance codes.
Although development of NIBRS began with a 1984 conference, a major impediment to the system’s usefulness is that the “pace commensurate with the resources and limitations of contributing law enforcement agencies” envisioned in 1984 has turned out to be extremely slow. As of September 2007, the Justice Research and Statistics Association2 estimated that only about 25 percent of the nation’s population is included in NIBRS-compliant jurisdictions. In all, about 26 percent of agencies that supply data to the UCR do so using the NIBRS format. Among the states that have not yet implemented NIBRS are California, New York, and Pennsylvania; in Illinois, the only NIBRS participant to data is the Rockford Police Department. Five states—Alaska, Florida, Georgia, Nevada, and Wyoming—have not yet specified any formal plan for participation in NIBRS.