The correlation between more police enforcement and fewer shooting incidents in NYC

In early 2021 I pointed out, which was a considered a radial concept by many at the time, that violence had indeed gone way up since the unrest following the murder of George Floyd.

I wanted to update the data in that post about the relationship between enforcement (or lack thereof) and violence. So I did.

Breaking it down by quarter shows heavy seasonal effects. So it’s more useful to compare every 4th bar (same quarter, different year) than every adjacent bar. 3Q 2019 vs 3Q 2020 is the most dramatic.

Here are the categories and numbers.

I picked the categories to ones that mattered and to try and limit enforcement to NYPD enforcement and not the enforcement of other agencies (like building and fire and health inspectors). Some of terms have shifted over time. Like “failure to comply with sign” has kind of morphed into “disobey any park sign.” Discon has all but disappeared but “congregates with other persons” has taken up some of the slack, going from zero to 111. The only low-level categories that have increased since 2017 are smoking in train station and bicycle on sidewalk.

The basic end of policing in the 3rd quarter of 2020 is pretty striking. It’s also when shootings reached their many-year high.

Sources: https://www.nyc.gov/site/nypd/stats/reports-analysis/c-summons.page and NYPD