Check out this Vox article on the impact of Black Lives Matter (BLM) protests on police homicides, other homicides, and property crime within the communities where protests occurred. It cites a study by Travis Campbell, a Ph.D. candidate in economics at UMass-Amherst with the following major findings for the period 2014-2019:

1) Police homicides in census areas where BLM protests took place were 10% – 15% less than if those deaths had followed the trend where BLM protests did not take place, after controlling for confounding factors like the local unemployment rate. That’s about 300 fewer uses of lethal force by police, or one less for every 4,000 BLM protestors. So far, so good, one might guess.

2) Other homicides increased by roughly 10% using the same basis of comparison, or somewhere between 1,000 and 6,000. This estimate is less precise for a number of reasons, and it was not the main focus of Campbell’s research. Still, using a value near the mid-point, say 3,000, yields one extra murder for every 400 BLM protestors! The effect seems to taper off after about four years.

3) Reported property crimes decreased by 8.4% in areas that had BLM protests, but the share of those crimes solved declined by 5.5%. Campbell interprets the latter as an indication of reduced policing intensity. Reports of crime might decline if confidence in the police declines post protest, but reduced effort by the police is also consistent with less reported property crime, less police engagement, and more homicide.

As Alex Tabarrok says:

“The explanation is consistent with what happened in Baltimore after the Freddie Gray protests and riots, namely arrests went down and murders went up.”

The research did not include data on the 2020 protests and riots following the death of George Floyd due to lags in reporting homicides and crime.

One of BLM’s primary objectives is to end “systemic racism” in policing, a problem that has no real empirical basis. Nevertheless, a reduction in deadly confrontations between police and blacks would seem to be a win (though the study doesn’t address the racial makeup of police homicides). But if that means less police engagement and a substantial increase in homicides in the community, the cost is obviously too high. Areas suffering from high homicide rates need more policing, not less. But yes, it must be good policing in partnership with citizens, and there are real reforms that could help.

BLM’s continued calls to “defund the police” are more about signaling lofty intent than about solving real problems. After all, that’s the perverse charm of the Marxism espoused by BLM, Antifa, and gentry leftists having class immunity to unintended (but predictable) consequences. You don’t really have to solve problems. You can just make them for others and take credit for trying!