Policing and crime: dynamic panel evidence from California

We exploit police and crime data from California over 26 years to construct a dynamic panel, which is then estimated using Arellano–Bover/Blundell–Bond techniques to address concerns about simultaneity, unobserved heterogeneity, and inertial effects in the policing-crime relationship. We find no evidence that increases in police staffing lead to meaningful reductions in crime through either deterrence or incapacitation. Estimates are not wholly supportive of a compelling relationship between prior criminal offending and current police staffing; providing suggestive evidence that, at least within our sample, simultaneity bias may be more modest in nature than has been previously supposed in prior studies.