State Gun Laws and County-Level Firearm-Related Suicide Rates

Importance Although studies on the potential benefits of firearm laws for the rates of firearm-related suicide have been performed at the state level, suicides are not evenly distributed across each state, and a more granular analysis at the county level would be better equipped to capture variation within states. Objective To examine the association between state firearm laws and county-level firearm-related suicide deaths among all 50 states from 2000 to 2023. Design, Setting, and Participants This cross-sectional study assessed data obtained from the Centers for Disease Control and Prevention WONDER database on annual county-level firearm-related suicide rates from 637 counties across all 50 US states from January 1, 2000, to December 31, 2023. The analysis used a panel design with a difference-in-differences, fixed-effects model. The model accounted for heteroskedasticity and adjusted for a range of sociodemographic covariates. Data were analyzed from February 1 to March 15, 2026. Exposures Eight firearm laws potentially associated with suicide risk were included: a minimum age of 21 years to buy a handgun, allowing law enforcement to petition courts for extreme risk protection orders, waiting periods for firearm purchases, handgun permit requirements, concealed carry permit requirements, violent misdemeanor prohibitions, “may issue” laws that give law enforcement discretion in approving applications for concealed carry permits, and laws to prevent child access to firearms. Main Outcome and Measures The primary outcome was a change in annual county-specific firearm-related and non–firearm-related suicide rates. Results The overall population of the 637 counties in the sample for 2023 was 250 million, representing 74.2% of the total US population. Among 10 893 county-year observations, the percentage change in firearm-related suicide rates was associated with the implementation of 5 state firearm laws, including extreme risk protection orders for law enforcement (−9.1%; 95% CI, −14.5% to −3.8%), violent misdemeanor prohibitions (−13.5%; 95% CI,–21.5% to –5.5%), minimum age of 21 years for purchasing a handgun (−9.2%; 95% CI, −11.6% to −6.9%), a permit requirement for purchasing a handgun (−6.7%; 95% CI, −10.6% to −2.8%), and child access protection laws (−8.3%; 95% CI, −11.0% to −5.7%). Conclusions and Relevance Findings of this cross-sectional study of county-level firearm-related suicide rates in all 50 states during a 24-year period account for county- and state-level factors that may influence suicide rates. Future research should use multilevel modeling to confirm these findings.