This story was published earlier this month but I didn’t see it until yesterday when the Daily Caller tweeted about it. Vox published the results of a “rigorous academic” study looking at the impact of Black Lives Matter protests on the use of force by police. The results haven’t been peer reviewed yet so take them with a grain of salt. But the research suggests the protests wind up doing more harm than good in the neighborhoods where they happen.

From 2014 to 2019, Campbell tracked more than 1,600 BLM protests across the country, largely in bigger cities, with nearly 350,000 protesters. His main finding is a 15 to 20 percent reduction in lethal use of force by police officers — roughly 300 fewer police homicides — in census places that saw BLM protests.

Campbell’s research also indicates that these protests correlate with a 10 percent increase in murders in the areas that saw BLM protests. That means from 2014 to 2019, there were somewhere between 1,000 and 6,000 more homicides than would have been expected if places with protests were on the same trend as places that did not have protests. Campbell’s research does not include the effects of last summer’s historic wave of protests because researchers do not yet have all the relevant data…

Omar Wasow, a professor at Princeton University who has done seminal research on the effect of protests, told Vox that the results are “entirely plausible” and “not surprising,” considering existing protest research.

Somewhere between 1,000 and 6,000 homicides is quite a large range. If you split the difference at 3,000, then the protests effectively cost 10 times as many lives as they save.

Most of the rest of the Vox piece looks at the possible mechanisms to explain both of these findings. So, for instance, there are three possible reasons offered that might explain the drop in police homicides. First, protests might spark reforms such as the use of body cams or community policing and that might in turn limit police shootings. But Vox notes there’s not a lot of evidence to support the claim that body cams change police behavior.

Another possibility is that civilians become more wary of police and may call them less as a result of protests. That seems like it would be relatively easy to test. Just look at the trend lines of 911 calls before and after protests. Vox does look at this later and notes that while some criminologists believe a drop in the reporting of lower level crimes does happen, some recent research found that “across a large number of cities, incidents, and analytic strategies well-publicized brutality incidents do not reduce 911 calls to report common property or violent crimes.” In other words, there’s some reason to think people aren’t pulling back from engagement with police.

The third possibility is the so-called Ferguson Effect, the idea that after significant protests police pull back and aren’t as aggressive when doing their jobs. And here Vox notes there is some research to support this:

Deepak Premkumar, a research fellow at the Public Policy Institute of California, found in recently released research that police do reduce their efforts following officer-involved fatalities: Theft arrests fall by 7 percent, and for “quality of life crimes” like disorderly conduct or marijuana possession, arrests decline by up to 23 percent (weed possession alone declines by up to 33 percent).

Fewer interactions with police means fewer busts that turn violent and fewer situations where guns are drawn and people are shot. And of course that could also potentially explain the increase in homicides in these same areas. Less aggressive policing may indeed mean fewer people shot by police, but it may also embolden criminals by reducing the risk they face for illegal behavior. And here, Campbell’s own research seems to support this. He found that the number of low level crimes cleared by police drops after major protests, exactly as if police aren’t trying as hard.

Vox wraps all of this up with a rather blithe conclusion noting that four years after protests the murder rates seem to return to normal. That may be so but it’s no help to the thousands of additional homicide victims or their families. Their lives obviously don’t go back to normal after four years.

It’s hard to see how anyone looking at this data could conclude that BLM protests are something any community should be happy about. If the outcome is a dramatic increase in violent crime for several years and a marginal decrease in police shootings, that doesn’t sound like a good bargain. In fact, it’s probably worse than the numbers suggest.

All of the additional homicides, again we can say 3,000 for the sake of argument, are murders that would not have happened if not for the protests. Those are people who would still be alive. The same can be said for the 300 people shot by police. But there’s an obvious difference. All of the 3,000 homicides that shouldn’t have happened were illegal and fundamentally unjust. Many are probably some kind of street justice with absolutely no public oversight (except for more street justice). On the contrary, the 300 police shootings will be investigated and will all face review and public scrutiny. So even apart from the body count, the police shootings represent a far better system if your goal is justice. In fact, even if the number of homicides was equal to the number of police shootings, the community would still be better off dealing with the police shootings.

Finally, there’s the media piece of this. Newspapers like the Washington Post have made a big deal about the claim that 93% of BLM marches are peaceful and downplaying that the remaining 7% have done substantial damage to cities and in terms of the number of injured police officers (around 2,000 last summer). But if research suggests BLM protests also result in disruptions that lead to thousands of additional murders how does that get reported? What if the marches are mostly peaceful but the result is streets that are anything but peaceful. Can BLM be criticized for this? My guess is the progressives who run the media won’t allow that even though they wouldn’t hesitate to do so if this were, say, findings about the outcomes of Tea Party protests.