Thread by @jonmummolo

Brett Stephens is crediting "Broken Windows" policing strategies like "Stop, Question and Frisk" (SQF) for the nationwide crime drop that began in the 1990s. Let's take a look at the evidence. 1/n

https://twitter.com/prageru/status/1177209958493913089

It is true that Broken Windows expanded in the mid 90s in NYC and crime also fell in that period. But crime also fell in cities across the country that did not embrace Broken Windows. 2/n

This is a classic case of confusing correlation with causation. You know what else closely tracks murder rates over time? Ice cream sales. Both tend to happen more often when it's hot outside. That doesn't mean banning ice cream will make cities safer. 3/n

I studied a NYC reform in 2013 that curtailed stop and frisk & increased rate of justified stops. A series of other reforms followed and stop rates plummeted. Murder rate continues to fall. City is the safest it has been in decades. 4/n

Paper in @The_JOP: tinyurl.com/ycy73ycn

Noting the continued decline of crime in NYC after stop and frisk's demise, a commendable piece by conservative columnist @rkylesmith in @NRO acknowledged ``We Were Wrong About Stop-and-Frisk.'' 5/n

Article: tinyurl.com/y9bwxo2d

Here is a 2012 study by Rosenfeld and Fornango on stop and frisk and crime. The study finds, ``few effects of SQF on robbery and burglary.’’ 6/n

Paper: tandfonline.com/doi/full/10.10…

MacDonald, @JFagan46 & Geller find a notable exception: SQF lowers crime if stops based on``probable cause...of criminal behaviors.'' Stops ``based on...suspicious behavior'' had no effect. Under expansive SQF, bulk of stops are ineffective. 7/n

Paper: journals.plos.org/plosone/articl…

Stop and Frisk is historically concentrated in Black communities where trust in police is already low. Lack of trust makes the job of police much harder. These tactics come at a cost, for both law enforcement and civilians. 8/n

The idea that Broken Windows tactics lower crime rates is not backed up by the data. In the absence of new and compelling evidence, we should stop repeating this folk tale. n/n