Paul G. Cassell is the Ronald N. Boyce Presidential Professor of Criminal Law and University Distinguished Professor of Law at the S.J. Quinney College of Law at the University of Utah. He is also the foremost scholar of the “Minneapolis Effect” reflecting the spike in murders following the death of George Floyd in Minneapolis on May 25. Professor Cassell describes the effect in the opening of today’s Wall Street Journal column “Homicide Stats Show ‘Minneapolis Effect.’” He writes:
Cities across the country suffered dramatic increases in homicides this summer. The spikes were remarkable, suddenly appearing and widespread, although often concentrated in disadvantaged neighborhoods. This year is on track to be the deadliest year for gun-related homicides since at least 1999.
The homicide spikes began in late May. Before May 28, Chicago had almost the same number of homicides as in 2019. Then, on May 31, 18 people were murdered in Chicago—the city’s most violent day in six decades. Violence continued through the summer. July was Chicago’s most violent month in 28 years. As of Sept. 1, murder is up 52% for the year, according to Chicago Police Department data.
Chicago’s shooting spike reflects what is happening in many major cities across the country. Researchers have identified a “structural break” in homicide numbers, beginning in the last week of May. Trends for most other major crime categories have remained generally stable or moved slightly downward.
What changed in late May? The antipolice protests that began across the country around May 27 appear to have resulted in a decline in policing directed at gun violence, producing—perhaps unsurprisingly—an increase in shootings.
He quantifies the effect:
My recent research quantifies the size of this summer’s Minneapolis Effect, estimating that reduced proactive policing resulted in about 710 more homicides and 2,800 more shootings in June and July alone. The victims of these crimes are disproportionately African-American and Hispanic, often living in disadvantaged and low-income neighborhoods.
Professor Cassell has posted his “recent research” in the paper that is accessible here at SSRN. A 68-page PDF version of his paper is posted here.
Professor Cassell counsels the restoration of preventive policing to overcome the effect. However, Minneapolis lacks the departmental manpower, the political will, and the civic support necessary to follow up on this obvious conclusion.