Understanding National Crime Data A comparison of data from the FBI and the National Crime Victimization Survey

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The narrative that the United States is in a historic violent crime wave has landed with some voters and reflects how media coverage of crime shapes public perception and people’s sense of safety. The most frequently cited national crime data comes from the Federal Bureau of Investigation (FBI), though it is not the only government data source. As many researchers and journalists have cautioned, the FBI’s police-reported crime data is troubled by inaccuracies and incomplete coverage. This brief explains why the FBI data is an inconclusive measure of crime in the United States and presents analysis of an additional, less-discussed source of crime data: the National Crime Victimization Survey (NCVS).

Key Takeaway

FBI crime data is not a reliable measure of people’s experiences of safety or harm and offers an incomplete view of violence trends. Instead, it measures law enforcement response to certain types of crime, and its creation involves discretion, interpretation, and estimation.

Publication Highlights

  • The increases in aggravated assaults reported by the FBI might have been, at least in part, a result of changes to crime classification by police agencies.

  • Many experiences of crime are never reported to the police and, therefore, are not counted in the FBI’s statistics.

  • Without greater transparency in its methods, it is impossible to determine the extent to which data released by the FBI is truly reliable or accurate.

Key Facts