NCJ Number
231660
Date Published
July 2000
Length
25 pages
Annotation
This analysis of the National Incident Based Reporting System (NIBRS) determines the effect of NIBRS on assault-rate estimates and identifies interesting reporting patterns for other types of crime.
Abstract
In the course of this analysis, the author addresses the following issues: the suppression of less serious offenses under the NIBRS hierarchy rule; the misapplication of the hierarchy rule; the need for more accurate reporting; changes to or restructuring of the definitions of rape, burglary, and assault; counting differences between States; and the role of data processing in maintaining uniformity of reporting. Since much of the analysis compares NIBRS data with summary Uniform Crime Reports (UCR) data, the report first lists the characteristics of summary UCR data and the characteristics of NIBRS data. The analysis focuses on both NIBRS and summary UCR aggregate crime counts within an agency for each year between 1991 and 1996 in which the agency reported 12 months of NIBRS data. Figures show the average percent difference in crime rate estimates when reported through NIBRS rather than summary UCR; percent of cases with a change of +5.5 percent or less when comparing NIBRS to summary UCR; and changes from 0 to 15 percent in index crime rates estimates when comparing NIBRS to summary UCR. The latter calculation is also shown for violent crime rate estimates and property crime rate estimates. The analysis also examines the effects of NIBRS on crime rate estimates for larger jurisdictions. In addition, the analysis compares NIBRS counts with NIBRS converted to summary UCR for homicide, assault, burglary, motor vehicle theft, and larceny.