Stop-Question-Frisks as a Crime Control Strategy? Results from a Space-Time Interaction Model

• In Event: Patterns of Crime in Space and Time

Abstract

Crime has been declining in New York City (NYC) since the early 1990s. The policing strategies of the New York City Police Department (NYPD) may have contributed to this dramatic crime drop, particularly through the widespread implementation of NYPD’s stop, question, and frisk (SQF) policy. Despite the controversy this policy has garnered, few empirical studies exist on the crime impact of SQFs. The findings of these studies, however, are based predominately on aggregated data at large geographic units (see Rosenfeld & Fornango, 2014; Smith & Purtell, 2008), which may mask or attenuate localized crime reductions. Empirical research showing that SQFs are highly concentrated at crime hot spots (Weisburd et al., 2014) further suggests that a more micro unit of analysis may be more appropriate for analyzing the effect on SQFs on the crime drop. The present study explores how SQFs and crime incidents in NYC interact in space and time by employing a spatiotemporal Ripley’s k-function, a test that relies on x-y coordinates of the exact locations of the incidents at a daily level. The analyses suggest a strong short-term deterrent effect of SQFs on crime, with little immediate areal displacement.

Authors

• Alese Wooditch, George Mason University

• David Weisburd, George Mason University / Hebrew University