Do Restrictive State Gun Laws Reduce Firearm-Related Suicides and Homicides?

This study asked whether restrictive state gun laws reduce firearm-related suicides and homicides. Researchers examined gun law scores from the Giffords Law Center (2017–2021), firearm death rates from CDC WONDER, and demographic data from the U.S. Census. They found that stronger laws were significantly associated with fewer firearm deaths overall (R² = 0.19, p < .001). The relationship was much stronger for suicide (R² = 0.70 in 2018 and 0.65 in 2022, p < .001) than for homicide (R² ranged from 0.14 in 2018 to 0.10 in 2022). Sociodemographic factors, such as poverty and unemployment, showed stronger links with homicide.

The Policy Scientist’s Perspective

This article in JAMA Network Open addresses an issue of profound national significance: the capacity of state-level firearm regulations to reduce deaths from both suicide and homicide. Its contribution lies in distinguishing between these two outcomes, demonstrating that stronger laws are most consistently associated with reductions in suicide, while homicide rates remain more sensitive to socioeconomic conditions. The data are robust, drawing on national sources over multiple years, and the analysis is careful. Yet the reliance on multivariate regression, while informative, limits causal inference. Stronger designs, such as natural experiments or randomized interventions, would enhance confidence in these findings.

Full Citation and Link to Article

Cornell, E., Roberts, B., Klein-Cloud, R., Nofi, C. P., & Sathya, C. (2025). State gun laws and firearm-related homicides and suicides, 2017–2022. JAMA Network Open, 8(7), e2519955. https://doi.org/10.1001/jamanetworkopen.2025.19955

Central Research Question

The study investigates whether stronger state gun laws are associated with lower rates of firearm-related mortality, with specific attention to the distinction between homicides and suicides. Previous research has generally assessed overall firearm mortality as a single measure, but this article asks whether laws operate differently depending on intent. The research aims to determine which categories of laws—such as regulations on firearm sales, restrictions on weapons, and accountability measures—are most strongly correlated with reductions in deaths, and whether socioeconomic and demographic conditions exert stronger influence over homicide than over suicide .

Previous Literature

The relationship between firearm regulation and mortality has been the subject of a substantial body of scholarship. Prior studies consistently demonstrate that states with stricter gun laws tend to experience fewer firearm deaths. For example, Siegel and colleagues (2019) found broad associations between stronger state firearm laws and lower overall firearm homicide and suicide rates between 1991 and 2016. Other research has highlighted the importance of specific policy levers such as child access prevention laws, background checks, and storage requirements. However, much of this literature has limitations. First, studies often use aggregated mortality measures rather than distinguishing among types of firearm death. Second, relatively few studies have explored how different categories of gun laws interact with demographic and socioeconomic factors. Finally, prior analyses have tended to rely on broad correlations without parsing whether some laws affect suicides more than homicides or vice versa. This research letter builds on these gaps by distinguishing firearm deaths by intent, examining multiple categories of laws, and controlling for sociodemographic variables .

Data

The study draws on three primary data sources. First, measures of state gun law strength were obtained from the Giffords Law Center, which produces annual “Gun Law Scorecards” rating states across ten categories of policy interventions. These include regulation of sales and transfers, restrictions on firearms in public places, accountability requirements for gun owners, and laws governing specific classes of weapons and ammunition. Second, mortality data came from the Centers for Disease Control and Prevention’s WONDER database, which provides annual firearm death counts and rates, disaggregated by intent (homicide, suicide, and unintentional deaths). For purposes of analysis, the study focused on homicide and suicide, given the relatively small number of unintentional deaths. Third, demographic and socioeconomic data were obtained from the American Community Survey’s five-year county-level estimates. These included measures of race and ethnicity, median income, education levels, insurance coverage, poverty rates, unemployment, and disability status. Combining these sources created a panel of county-level firearm death rates paired with state law scores and county demographics, covering the years 2017–2021 .

Methods

The analysis followed the STROBE guidelines for cross-sectional observational research. After merging Giffords law scores with CDC mortality data and ACS demographics, the authors conducted both univariate and multivariate regression analyses. The dependent variables were crude firearm death rates by intent (homicide or suicide). Independent variables included overall state gun law strength and scores for the ten policy categories. Control variables were demographic and socioeconomic characteristics at the county level. R² values were used to assess strength of association, with values above 0.10 considered meaningfully strong. The key multivariate results were presented as β coefficients (slopes) showing the magnitude of change in firearm death rates associated with incremental increases in gun law strength, adjusted for sociodemographic factors. The statistical threshold for significance was set at one-sided p = .05. The authors emphasize that results should be interpreted as correlational rather than causal, reflecting the limitations of cross-sectional design and regression-based methods .

Findings/Size Effects

The results demonstrate that stronger state gun laws are consistently associated with reduced firearm mortality overall, though the magnitude of this effect differs by intent. Across all years, cumulative state law strength correlated with lower crude firearm death rates (R² = 0.19; p < .001). From 2018 to 2022, gun law scores were strongly correlated with reductions in suicide, with R² values ranging from 0.703 in 2018 to 0.649 in 2022, all highly significant (p < .001). In contrast, the association with homicide was much weaker: R² values ranged from 0.144 in 2018 (p = .01) to 0.099 in 2022 (p = .04) .

Multivariate results highlight the differences across law categories. For suicides, the strongest negative correlations were found for regulation of sales and transfers, firearm restrictions in public places, gun owner accountability, and limits on classes of weapons and ammunition. For homicides, the laws most correlated with reductions were those concerning consumer and child safety and investigation of gun crimes. However, even these effects were weaker than the associations observed for suicides .

By contrast, several sociodemographic factors were more strongly correlated with homicide than any single category of gun laws. For example, counties with higher poverty rates, greater proportions of uninsured individuals, and higher unemployment experienced substantially elevated firearm homicide rates. R² values for poverty and homicide reached 0.50, with a slope (β) of 0.71, indicating large effect sizes compared to those associated with gun laws. Similarly, the proportion of Black residents was highly correlated with higher homicide rates (R² = 0.65; β = 0.81), underscoring the role of structural inequities and socioeconomic disadvantage .

Table 2 from the article quantifies these associations. The total Giffords law strength score showed a significant negative relationship with overall firearm mortality (β = –0.282; p < .001). For suicides, the slope was slightly larger (β = –0.292; p < .001), while for homicides it was smaller (β = –0.144; p < .001). Individual categories such as “Gun Owner Accountability” (β = –0.260 for suicide; –0.108 for homicide) and “Firearms in Public Places” (β = –0.280 for suicide; –0.141 for homicide) illustrate how specific interventions align differently with outcomes .

Conclusion

This research letter makes two important contributions to the literature. First, it confirms that stronger gun laws are associated with reduced firearm mortality, consistent with prior work. Second, it demonstrates that the strength of association is substantially greater for suicide than for homicide. This distinction highlights the importance of tailoring policy interventions to the specific drivers of different forms of firearm violence. For suicides, laws that limit access to firearms during crises, regulate sales and transfers, and impose accountability on owners appear especially effective. For homicides, the study finds that structural socioeconomic factors—poverty, unemployment, racial disparities, and lack of insurance—exert stronger effects than the legal environment. These findings suggest that reducing homicide will require broader interventions that extend beyond gun policy, such as economic mobility initiatives, community-based violence prevention, and expansion of health and social services.

The authors acknowledge limitations, including the reliance on cross-sectional data, county-level aggregation rather than individual-level analysis, and exclusion of nonfatal firearm injuries. Enforcement variability and the relatively short timeframe of analysis also constrain interpretation. Nevertheless, by disaggregating firearm deaths by intent and analyzing multiple categories of laws alongside demographic factors, the study provides a nuanced and policy-relevant understanding of how legal frameworks interact with social determinants of violence.