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.

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Background by Sukari Stone

Complaints against CPD officers are routed through several investigative bodies. Most complaints are investigated internally. Minor allegations are investigated by an officer’s supervisors, while more serious complaints are handled by the CPD’s Bureau of Internal Affairs.

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Complaints by Sukari Stone

The number of accusations (and complaints) filed declines greatly over time, reaching a peak of 1,165 accusations in a single month in August of 2002, and steadily dropping until the lowest complete month of data, May of 2016, with only 190 accusations. There are two main periods in this data set, before IPRA (Indepedent Police Review Authority) and after IPRA, which was announced on r and put in place on r.

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Accused Officers by Sukari Stone

The composition of officers accused of misconduct is roughly representative of the racial composition of the police force as a whole, but the upper ranks of the CPD are underrepresented (as would be expected) and thus older, white male officers are underrepresented. Additionally, female officers are noticably underrepresented relative to male officers across all races.

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Unique Officers by Sukari Stone

White officers comprise a majority of the officers accused of misconduct (51.48%), while blacks make up a slightly larger share (24.77%) than Hispanics (20.73%). Black officers are more likely to be female (31%) than other races, reflecting the relative make up of the CPD in general. In terms of age, black officers (48.83) are older than whites (45.67), and Hispanics (43.38) are the youngest. Given the age and gender differences between officers of different races, some differences in number of accusations is to be expected.

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Complaint Outcomes by Sukari Stone

Of the 49,690 accusations with identified officers in the period of examination, 44,895 have non-missing Recommended and Final Findings, non-missing investigation close dates, and had between 2008 and 2015. Accusations with missing findings are either the result of poor data collection, or, more likely, an investigation being incomplete, and thus no recommended or final finding is recorded. There are 5 outcomes: Sustained (SU), Not Sustained (NS), Unfounded (UN), Exonerated (EX), and No Affidavit (NAF). These terms, other than No Affidavit, which means the complainant did not sign an affidavit and thus no investigation was likely to take place, are described below in the 2017 DoJ Report (not that the report uses ‘complaint’ in place of ‘accusation’):

“Sustained” means the complaint was supported by sufficient evidence to justify disciplinary action. “Not sustained” means the evidence was insufficient to either prove or disprove the complaint. “Unfounded” means the facts revealed by the investigation did not support the complaint (e.g., the complained-of conduct did not occur). “Exonerated” means the complained-of conduct occurred, but the accused officer’s actions were proper under the circumstances.

Outcomes for Civilian vs. Officer Complaints

A complaint (containing one or many accusations) can be filed by either a civilian (non-police officer) or a police officer against a member of the CPD. All accusation outcomes within a complaint do not have to be the same. From the plots below, it is clear that civilian complaints are much more likely to not have an affidavit signed compared to officer complaints. Similarly, given an affidavit is signed, officer complaints are fairly likely to end in a sustained (SU) finding.

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Outcomes by Officer Demographics

Given an affidavit was signed, officer complaints maintain an astoundingly larger sustained rate (50.76%) than civilian complaints (4.14%). However, in both officer and civilian filed complaints, black officers accused of misconduct are more likely to be sustained against. Accusations by officers against black officers are 57.7% sustained, compared the sustained percent of white and Hispanic officers (44.86 and 51.11, respectively). In civilian complaints, accusations against black officers are 5.98% sustained, compared the sustained percent of white and Hispanic officers (3.43 and 3.89, respectively).

Outcomes Over Time

Over the period of analysis, complaints resulting in No Affidavit (NAF) hold a consistent plurality (56.8% of all outcomes), while the number of complaints that are sustained (SU) is abysmally low (5.76% of all outcomes). The share of complaints resulting NAF begins at 59.31% of outcomes for complaints in 2008 and declines steadily to a low of 47.08% in 2011, then rises steadily to 47.08% in 2015. The rate of sustained findings remains relatively constant, only fluctuating between 4.38% and 8.5% in 2010 and 2013, respectively.


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Complainants and Victims by Sukari Stone

In the complainant and victim data sets, a total of 47,042 complaints have any complainant and 16,847 complaints have any victim information. Occassionally, there are multiple victims and/or complainants. Complainant and victim information is very sparse before January of 2000, and, though complainant information is more common than victim information, both become substantially more common. Complainant information is significantly more common than victim information until January 1, 2015, after which victim information is more common.


Complainants and Victims in Sample

Focusing on the sample of complaints, it is clear that victim information is inconsistent for both civilian and officer filed complaints, but complainant information is almost fully known for officer filed complaints. Civilian filed complaints also have relatively consistent complainant information, but there is a considerable drop off in 2015.


Complainants and victims both tend to be male more commonly than female, but in both cases black complainants and victims are more commonly female than other races. Unsurprisingly, victims tend to be younger than complainants, as a young victim may not be their own complainant. In total racial composition, black individuals comprise 63.51% of know complainants and 71.05% of known victims. The next highest, whites, only comprise 23.58% of complainants and 12.85% of victims, followed by Hispanics at 23.58% of complainants and 12.85%. The numbers for Hispanics are surprisingly low, given Chicago being roughly 30% black, white, and Hispanic.


Complainants and Accused Officers

Considering the more complete information of complainants, we will continue focusing on their information.

The table below, displaying complainant racial breakdown with respect to officer race, shows a not unexpected relationship. Black complainants make up a larger share of black officer accusations (77.55%), while Hispanic complainants maintain their largest share in Hispanic officer complaints (17.29%).


Complainants and Outcomes

The sustained rates for all civilian accusations are miniscule compared to those of officer complaints. This section only includes the 46052 accusations with non-missing final findings. Focusing on accusations with affidavits, white civilian-complainant accusations are sustained at a rate of 9.66%, which is 3 times the rate of black civilian-complainant accusations (3.17%) and 2.3 times the rate of Hispanic. civilian-complainant accusations (4.22%). This is a considerable disparity. In officer filed accusations, there are still racial disparities, but to a lesser extent. Black complainant-officers have their accusations sustained at the lowest rate of 43.14%, followed by Hispanic officers (50.72%) and White officers (53.94%). Interestingly, Black officer complainants sign affidavits at a lower rate than other officers (11.56% compared to 8.88% and 7.66% for Hispanic and white officers, respectively).

Officer Witnesses by Sukari Stone

Some officers act as witnesses in the investigations of other officers accused of misconduct. 11,345 unique officers with identifiable information were witnesses in 12,169 complaints in 27271 witness-complaint combinations. 3,466 of these complaints are in the sample of analysis, and will be used in the rest of this section.