“Ferguson effect” documented in Chicago

Rob Arthur and Jeff Asher at FiveThrityEight show that arrests have declined and gun violence has spiked since the release of the video showing Laquan McDonald being shot and killed by the police. This is evidence of the “Ferguson effect.”

Arthur and Asher explain:

After some cities saw a rise in crime last year, police chiefs and even the head of the FBI suggested that the United States was experiencing a “Ferguson effect”: Police officers sensitive to public scrutiny in the wake of protests over the 2014 police killing of Michael Brown in Ferguson, Missouri, were pulling back on police work, the theory went, and emboldened criminals were seizing their chance.

Some dismissed this theory or expressed lots of skepticism given the volatility of crime statistics. According, to Arthur and Asher, however:

The spike in gun violence in Chicago since the end of November. . .is too sharp to be explained by seasonal fluctuations or chance. There have been 175 homicides and approximately 675 nonfatal shooting incidents from Dec. 1 through March 31, according to our analysis of city data.

The 69 percent drop in the nonfatal shooting arrest rate and the 48 percent drop in the homicide arrest rate since the video’s release also cannot be explained by temperature or bad luck. Even though crime statistics can see a good amount of variation from year to year and from month to month, this spike in gun violence is statistically significant, and the falling arrest numbers suggest real changes in the process of policing in Chicago since the video’s release.

(Emphasis added)

The Ferguson effect isn’t unique to Chicago:

A similar decline in police activity and increase in violence occurred in Baltimore after protests over the death of Freddie Gray, who died in police custody. Likewise, police activity in New York City slowed down dramatically after police killed Eric Garner. In the case of the New York Police Department, some news outlets suggested that the slowdown was a large-scale, organized protest against interference by the mayor.

Arthur and Asher find little evidence of an organized police slowdown in Chicago. However, “in both public statements and private conversations, former and current Chicago police officers, crime analysts and journalists have described a climate of low morale and hesitation among officers that has led to fewer arrests.”

The authors quote Roseanna Ander, an executive director at the University of Chicago Crime Lab. She finds that “proactive” policing, including street stops, that is designed to prevent crime has diminished, as officers seek to cut down on their discretionary interactions with civilians. “Certainly they’ll respond to 911 calls … but if you have a group of guys on the corner and you think you have probable cause to stop them and see if one of them has a gun, you’re probably not going to do that,” Ander says.

The diminution of proactive policing dates back to the release of the McDonald video. A police department spokesman attributes it to a new form that must be filled out after some interactions with members of the public. This requirement is the result of the city’s August 2015 settlement with the American Civil Liberties Union over the department’s “stop and frisk” program.

It’s logical to suppose that the paperwork requirement might reduce interaction with the public. However, Arthur and Asher point out that the requirement was implemented 38 days after the release of the Laquan McDonald video. By that time, the overall arrest rate had fallen from 26 percent to 19 percent. Since then, the overall arrest rate has risen slightly.

Reducing police interaction with the public will reduce the number of cases in which the police acts abusively. But the evidence is that, not surprisingly, reduced interaction will lead to an increase in violent crime, including gun violence.

Given the rarity of unjustified police shootings, it is obvious that policies and attitudes that discourage proactive policing will result in a very bad trade-off. And the trade-off will be worst for residence of low income and minority-centric neighborhoods where violent crime and gun violence are the most intense.