Nearly 20 Years Since the Federal Ban: Can State-Level Assault Weapon Prohibitions Fill the Void? Comparative...

Few states established assault weapon bans (AWBs) after the federal AWB expired. The effectiveness of state AWBs as well as neighboring state legislation, in reducing the local prevalence of assault weapons (AWs) or in reducing overall shooting lethality is unknown.

We queried the Gun Violence Archive (2014-2021) to identify US firearm injuries and fatalities. Shooting case fatality rates were compared among states with and without AWBs, as reported in the State Firearm Laws Database. Data on recovered firearms was obtained from the ATF Firearms Trace Database and used to estimate weapon prevalence. Recovered firearms were classified as AWs based on caliber (7.62 mm, 5.56 mm, 0.223 cal). We performed spatially weighted linear regression models, with fixed effects for state and year to assess the association between geographically clustered state legislation and firearm outcomes.

From 2014 to 2021, the US shooting victim case fatality rate was 8.06% and did not differ among states with and without AWBs. The proportion of AWs to total firearms was 5.0% in states without an AWB and 6.0% in states with an AWB (mean difference [95% CI] = -0.8% [-1.6% to -0.2%], P = 0.03). Most recovered firearms in AWB states originated from non-AWB states. On adjusted models, there was no association between state-level AWB and firearm case fatality; however, adjacency to states with an AWB was associated with lower case fatality (P < 0.001). Clustered AWB states with shared borders had lower AW prevalence and fatality rates than the rest of the US.

Isolated state AWBs are not inversely associated with shooting case fatality rates nor the prevalence of AWs, but AWBs among multiple neighboring states may be associated with both outcomes.