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Quasi-experimental study finding no localised gun crime or call reduction after gun buybacks in Philadelphia
Jerry H Ratcliffe1, Marc Huffer2
1Department of Criminal Justice, Temple University, Philadelphia, Pennsylvania, USA jhr@temple.edu.
Introduction:
Gun buyback programmes have been popular in the USA since the 1970s. Studies show that they have no effect on citywide gun crime rates, but more microlevel examinations around gun buyback locations have not been conducted. This study tests for local effects of 34 Philadelphia, PA buyback events at 30 locations between 2019 and 2021.
Methods:
We analysed all gun-related crime events and gun-related calls for service attended by the police from 2019 to 2021. Multilevel models with an autoregressive residual structure were estimated on weekly gun crime and call event intensity (inverse distance weighted) totals across a range of distances (4000-8000 feet). Impacts of a gun buyback event were estimated for 1-4 weeks postevent.
Results:
Statistically significant weekly increases in gun event intensity are associated with seasonality and after the murder of George Floyd. Gun event intensity was not significantly affected by gun buybacks. Across 20 sensitivity tests of different distances and time periods (4000-8000 feet and between 1 and 4 weeks), gun buybacks were not statistically associated with any localised reduction in the intensity of gun crimes and calls.
Conclusions:
Extant research has failed to uncover any effect of gun buybacks on citywide gun crime rates. The current results now contribute a lack of evidence at the local level to this literature. While gun buybacks remain popular with politicians and the public, this study adds to the ongoing question of whether buyback funds could be better spent more effectively.
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