Reported Crime Frequencies: A Statistical Comparison of State Crime Reports and the UCR

Prior research suggests there are inconsistencies between the UCR and other National-level crime data sources. Less research has tested whether similar inconsistencies exist between UCR and State annual crime reports. The current study compared 48 U.S. State’s Part I offense counts to the FBI’s UCR’s Part I offense counts for the years 2000–2018. Paired samples t-tests revealed significant differences for specific Part I offense counts as reported by individual States and the UCR. Percentage differences further indicated that the magnitudes of differences were substantively meaningful. Pairwise correlations indicated strong linear associations and convergence between State and UCR Part I offenses Nationally, but convergence diminished when assessing individual States. Frequency and percentage differences were treated as dependent variables in multivariate models. Results from OLS regressions suggest certain State-level factors significantly predict the observed differences between State and UCR reported Part I offenses. These results reveal that inconsistencies exist between two official data sources which have the same origin.