Follow-Up on CPD Assault-Related Crime Statistics

The City of Chicago Office of Inspector General (OIG) has completed a follow-up to its April 2014 audit of the Chicago Police Department’s (CPD) classification and summary reporting for assault-related crimes in 2012. OIG concludes that CPD has implemented corrective actions related to the original audit findings.

The purpose of the 2014 audit was to determine if CPD accurately;

  • classified assault-related crimes under CPD guidelines
  • reported crime statistics in CompStat reports and Illinois Uniform Crime Reporting (I-UCR) submissions.

The audit found that CPD reported all required assault-related incidents in CompStat reports, but misclassified 3.1% of assault-related incidents, which was under the 10% rate that the Federal Bureau of Investigation Criminal Justice Information Services (FBI/CJIS) stated was acceptable for agencies participating in the UCR program.*

We also found that CPD did not follow I-UCR rules, resulting in a 21% error rate in incident reporting and a 24% underreporting of victim offenses in the incidents sampled. Finally, we found that CPD incorrectly applied the I-UCR reporting rule regarding crimes against protected persons, thereby underreporting aggravated assaults and aggravated batteries to I-UCR by 5.7% and 3.2%, respectively.

 In March 2015, OIG inquired with CPD regarding the status of the corrective actions the Department committed to in response to OIG’s audit and any other actions it may have taken. Based on the Department’s follow-up responses, OIG concludes that CPD has fully implemented the corrective actions it committed to in 2014.


* OIG did not evaluate whether the 10% error rate deemed acceptable by the FBI for participating agencies constituted an acceptable error rate for other users of crime statistics. Our reference to it therefore should not be construed as an endorsement, validation, or rejection of it.