Short Take: Is There A “Minneapolis Effect”?

There are murders. There are shootings. They happened after the protests, riots and lootings in Minneapolis following the killing of George Floyd. Paul Cassell calls it the “Minneapolis Effect.

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.

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.

But that’s half a story, because shootings and murders increased, but not other crimes.

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.

Cassell explains the increase in shootings and murders as a direct consequence of the anti-police protests.

The sequence of events is straightforward. George Floyd’s death while in police custody in Minneapolis produced demonstrations against the police in major cities from coast to coast. As a result, officers in most cities had to be redeployed from their normal duties to help manage the protests, some of which turned violent.

Even as the demonstrations abated, what is commonly called “proactive” policing declined. Police department data show that street and vehicle stops in Minneapolis and Philadelphia dropped sharply in June. In Chicago and New York, arrests declined steeply. And in cities around the country, both law-enforcement and citizen reports suggest a general reluctance by officers to engage in hot-spot and other enforcement efforts that are most effective in deterring gun violence.

Notably absent from this sanitary connection is that police haven’t been directed to stop doing their job. There has been no order from on high telling them to not engage in “proactive” policing or, if you’re less adoring of police than Cassell, just doing the banal work of active policing in accordance with law and with respect toward the constitutional rights of people that some of us would really like to see as part of the job.

If cops’ feelings are hurt, such that they don’t want to do the job of policing because someone won’t give them a tummy rub, or the “Ferguson Effect” invoked by Heather McDonald to excuse the cops from not earning their paycheck, that’s a separate problem. Tossing black kids against walls just in case they might have a gun on them might be called “proactive” policing by some like Cassell, but that’s not the alternative to an unofficial slowdown by cops who just don’t feel like trying too hard when the public doesn’t show them the love they desire.

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.

It would be one thing if the shootings, the killings, were directed against the people who are being blamed for “systemic racism,” but that’s not the case now anymore than it was the case the last time murders were high.

But why not robberies? Why not other serious crimes? Why only shootings and murders? And why in black and Hispanic communities? Shootings are either about one person wanting to harm another person for some personal issue, or fights over turf. Other crimes like robberies are about getting stuff for free. Why don’t people want free stuff, but want dead people?

The cops failing to do their job may or may not be the problem, and if it’s happening, a management problem in need of fixing. But nothing about Cassell’s “Minneapolis Effect” explains why murders are up and not the other serious crimes that serve to get people free stuff. While giving the phenomenon a name might be a cool way for Cassell to ride on Heather McDonald’s coattails, it fails miserably to explain what’s happening at the moment. And what’s happening at the moment makes no sense.

21 thoughts on “Short Take: Is There A “Minneapolis Effect”?

  1. delurking

    Thank you. This stuff should stay in academic journals where it belongs. My entire life there have been all sorts of social scientific studies on why crime is rising or falling in any given period, and none of them have ever tried to account for the myriad changing features of society that might be the cause. It’s removal of lead from gasoline! It’s legalized abortion! It’s broken windows policing! Paging Andrew Gelman.

  2. Richard Kopf


    “And what’s happening at the moment makes no sense.” So it is that you brilliantly end your post on Cassell.

    Your earlier post today entitled “New York City In the Rearview Mirror” might end with the exact same gut punch. “And what’s happening at the moment makes no sense.”

    The connection I see between the essence of your two posts scares me. I dearly hope that my fear is generated only because old fools like me see things that aren’t there.

    All the best.


  3. Skink

    Cassell did some misapplying. His conclusion linking the increase in killings comes from data in a study of the virus effect. It’s not surprising data. Residential burglaries and robberies are down because there are more people at home all day and night. Domestic violence is up for the same reason. Thieving from businesses is up because it’s easy to burgle from a closed store or restaurant. Why would gun crimes be up? A bunch of guns are found before the shootings in cars during traffic stops, which weren’t happening because one would have to hang a human head from the bumper to get pulled over. Additionally, no stops gives a sense of criminal security.

    But, according to the study:
    “There appears to be a rough cyclical pattern and a very slight upward trend in the homicide rate over time. The model estimated a structural break near the end of May 2020, after which the homicide rate increased by 37% through the end of June. The rise in homicide was led by three cities: Chicago,
    Philadelphia, and Milwaukee.”


    “Rates of gun assaults, which are aggravated assaults committed with a firearm, rose at the end of May, according to data from 17 cities, with Chicago experienced the largest increase in gun assaults. But the increase was not substantially greater than that recorded the year before.”

    Are they measuring gun violence year-over-year, or just comparing to April? It seems the latter. Gun violence went up in the Summer? That’s only happened since Jesus left the manger.*

    I read Cassell’s abstract, but have no idea how he concludes the crime numbers reflect a “Minneapolis Effect.” The virus increased certain criminal opportunities and reduced others.

    You’re right, it doesn’t make sense, but that’s because the conclusion is flawed.

    *Data isn’t available for all years, so I might be making this up.

    1. phv3773

      I doubt cops ever took enough guns off the street to make a difference. More likely, it’s that more people are carrying guns.

  4. Bob

    The reliability of crime statistics tends to be inversely proportional to the severity of the crime. Sure, the authorities can write off some killings as suicides and accidents, but the reporting rate for murders is pretty darn close to the actual number of murders. Shootings? Probably pretty close, at least when someone actually gets shot. From there, it drops off precipitously.

    So I’d propose that it’s quite possible that lots of other crimes are actually increasing, too, but aren’t indicated by the statistics because they’re not being reported or discovered. Unfortunately the victimization surveys won’t be out for a few years.

    1. SHG Post author

      Please don’t do this. It’s possible. It’s also far more possible they aren’t. This is reddit level crap and has no business here.

  5. Drew Conlin

    I think everyone should read [Deleted]. Her contention of the under policing in violence regarding murder etc and over policing petty crime etc in black neighborhoods is what I thought of reading this piece.

    1. SHG Post author

      That’s nice that you think so. Start your own blog and let people know, but never use my comments to promote anything.

  6. Jake

    This post reminds me that back in July the Portland Police Beureau disbanded their Gun Violence Reduction Team. At the time, the local papers connected the decision to the ongoing unrest. At the time it struck me as an odd decision if it was truly and officially to placate the protesters. Overly specific, a drop in the bucket in terms of defunding, and sure to negatively impact poor/minority communities first and worst.

    Now the conspiratorial cynic in me is wondering if it wasn’t part of some larger, coordinated pattern designed to ‘show them’ what happens when the police pull out of their communities.

    Before calling me a loon, it’s well known the NYPBA coordinated a “virtual work stoppage” to Protest DeBlasio’s rhetoric in the wake of Eric Garner. Could this simply be a scheming evolution of the former strategy?

  7. John Barleycorn

    Well what if I told you it actually does make sense?

    And since you are becoming a part time economist, as of late, esteemed one, let me put your xenophobia of the unknown/ “this doesn’t make any sense”, in economic terms:

    Capitol is tripping over its own Bounded Rationality in terms of class stratification.

    The FED has voided the Lipstick Effect, which has in effect created some unanticipated consequences. None of those consequences are good for Main Street.

    Tragedy of the Commons back stops are hamstringing price discovery across the board to somehow protect the status quo while Tragedy of the Anti-Commons is hamstringing everyone having nice things at an accelerated rate.

    Perverse Incentives are becoming acceptable and even encouraged outside of government projects and spending. Them fucking guilds-whacha-gonna-do!

    Information Asymmetry is even a thing with your utility company these days. How is that even possible in a civilized country that isn’t some sort of twisted train wreck waiting on the mail to arrive?

    And finally, the Cobra Effect is summarily ignored at the ballot box on both sides of the isle and everyone still expects a different result.

    In other words, hippopotomonstrosesquippedaliophobia is a word for a reason and the joke will be on you and all those that keep underestimating the rage effect, let alone start rationally trying to figure out a way to vent the kettle and build some off ramps.

    The kiddos aren’t stupid even if they are currently just throwing their spaghetti against the wall.

    Do the Math-s, its hard and all… but if you don’t do the Math-s the wheels might actually just fall off the bus…

      1. John Barleycorn


        The future is in the return of the Zine, esteemed one, the innertubes and Harper Collins are becoming obsolete as we speak.

        You just don’t get out of the house often enough, or travel widely enough when you do, to see it…

        Happy twittering, and good luck with that… 😉


        1. SHG Post author

          The misspelling wasn’t the issue. I just don’t get the joke. If I did, maybe I would find it funny. Maybe not. But I just don’t see a joke there.

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