A series of highly publicized deadly-force incidents involving minorities has focused media and public attention on police practices. There has been much speculation that this increased criticism has led some law enforcement agencies to pull back, possibly contributing to rising crime in many cities, an alleged relationship that has come to be termed the “Ferguson effect,” criminologists John Shjarback, Scott Decker, Scott Wolfe and David Pyrooz write in the Washington Post. Our understanding of this kind of decline in proactive law enforcement — known as “de-policing” — is long on guesswork and anecdote but short on data and research.
In 2015, then-FBI Director James Comey made headlines when he suggested in a speech to the University of Chicago Law School that “a chill wind [is] blowing through American law enforcement over the last year. And that wind is surely changing behavior.” He was speaking a little more than a year after Michael Brown, an 18-year-old African American man, was fatally shot by an officer in Ferguson, Mo. Comey said it was his “strong sense” the recent spikes in violent crime in some cities were connected to such de-policing. What do the numbers say? For a study published in the Journal of Criminal Justice, the criminologists examined data on police activity in Missouri before and after Brown’s death. Police departments in Missouri are obligated by state law to submit data on traffic stops, including whether a search was conducted, contraband (such as drugs or weapons) was found or an arrest was made. Was there a change in police behavior? In Missouri, more than 100,000 fewer vehicle stops were made in 2015 than in 2014, a 6 percent reduction. This was a significant contrast to changes in stops between 2013 and 2014, when just a 2,000-stop swing was recorded. In 2015, something was happening in Missouri that could not be attributed to normal fluctuation.