Abstract
About 1,000 civilians are killed every year by a law enforcement officer in the USA, more than 90% by firearms. Most civilians who are shot are armed with a firearms. Higher rates of officer-involved shootings (OIS) are positively associated with state-level firearm ownership. Laws relaxing restrictions on civilians carrying concealed firearms (CCW) have been associated with increased violent crime. This study examines associations between CCW laws and OIS. We accessed counts of fatal and nonfatal OIS from the Gun Violence Archive (GVA) from 2014-2020 and calculated rates using population estimates. We conducted legal research to identify passage years of CCW laws. We used an augmented synthetic control models with fixed effects to estimate the effect of Permitless CCW law adoption on OIS over fourteen biannual semesters. We calculated an inverse variance weighted average of the overall effect. On average, Permitless CCW adopting states saw a 12.9% increase in the OIS victimization rate or an additional 4 OIS victimizations per year, compared to what would have happened had law adoption not occurred. Lax laws regulating civilian carrying of concealed firearms were associated with higher incidence of OIS. The increase in concealed gun carrying frequency associated with these laws may influence the perceived threat of danger faced by law enforcement. This could contribute to higher rates of OIS.