Introduction / by Sukari Stone

This is a general summary of the complaint data received via Freedom of Information Act (FOIA) requests to the Chicago Police Department (CPD) and the Independent Police Review Authority (IPRA), which was received in November of 2016. This data set contains information on complaints filed against police officers by other police officers and civilian, the classifications and outcomes of those complaints, complainants, victims, police officers acting as witnesses, and investigators. This is summary is meant as a brief overview of the complaints data, including trends, data quality issues, and historical context.

The complaints in this data correspond to incidents occuring between January 1, 2000 and June 17, 2016. There are a total of 109,339 complaint registry (CR) numbers in this data. A single CR number will be referred to as a ‘complaint’; a single complaint may name zero, one, or multiple officers, and each CR x officer combination will be referred to as an ‘accusation’, generally referring to accusations with identified officers; while in reality, a single accusation may be comprised of multiple ‘allegations’, meaning an officer in a complaint can be alleged to have committed multiple infractions (e.g. a single CR x officer combination having excessive force, uniform violation, and failure to provide services allegations) but in our data this level of granularity does not exist, so every accuation only has 1 allegation.

As noted, single complaint can correspond to multiple officers accused of misconduct. In total, there are 67,446 unique CR numbers resulting in 125,581 accusations filed against 16,021 CPD officers. The data on the victims of these complaints is more sparse than that of the accused officers. Only 16,847 complaints have victim information, and 47,042 complaints have complainant information. 11,346 officers are listed as witnesses for 12,606 unique complaints.

Due to the time frame of this data, it encompasses multiple oversight regimes for the Chicago Police Department. As of 2007, with the introduction of IPRA ….. EXPLAIN… a complaint can be filed….

The data set provided is by no means complete for various reasons: some complaints (41.893%) have no accused officer as they were not identified by the complainant; complainant and victim information are both rare before IPRA, but victim information remains less common than complainant information until the end of the data; complaint categories may not be accurate due to changing codes over time. Such inconsistencies and holes are common and will be more adquately explored in the rest of the document, but the full extent of the data’s incompleteness is not known.