110,000 Preventable Deaths: The Most Impactful Gaps in Firearm Suicide Prevention Laws 2010-2019

We sought to identify which absent firearm laws would have prevented the most firearm suicides (FS) in each state of the US.

Prior studies suggested efficacy for FS prevention varies greatly between different firearm laws. However, this body of work did not probe how this efficacy may differ by state.

This state-level, retrospective cohort study of firearm laws among the contiguous United States from 2010-2019 used Poisson models for the association between state FS per 100,000 population and implementation of state firearm laws lagged by 7 years, spatially weighted total firearm laws in surrounding states, and state demographics. These models were applied to each absent law in each state to estimate the reduction in FS associated with law implementation. The law associated with the greatest reduction in each state was the most impactful missing law.

Eight of 12 law categories were significantly associated with decreased FS rates. The largest associated reductions in FS were with child access prevention, or CAP (IRR 0.53; 95% CI 0.48-0.59; P<0.001), and concealed carry permitting, or CCP (IRR 0.59; 95% CI 0.54-0.65; P<0.001). Five states had all law categories for the study duration, and CAP and CCP were the most impactful missing law categories in 22 (51%) and 9 (21%) of remaining states, respectively. A total of 114,106 FS were associated with all states not having implemented their most effective missing law category across the study period.

This study found that FS rates in most states would have decreased most with passage of CAP or CCP, which can inform policymaking in respective states.