By Rosanna Smart

Background

Despite growing evidence about how state-level firearm regulations affect overall rates of injury and death, little is known about whether potential harms or benefits of firearm laws are evenly distributed across demographic subgroups. In this systematic review, we synthesized available evidence on the extent to which firearm policies produce differential effects by race and ethnicity on injury, recreational or defensive gun use, and gun ownership or purchasing behaviors.

Main body

We searched 13 databases for English-language studies published between 1995 and February 28, 2023 that estimated a relationship between firearm policy in the USA and one of eight outcomes, included a comparison group, evaluated time series data, and provided estimated policy effects differentiated by race or ethnicity. We used pre-specified criteria to evaluate the quality of inference and causal effect identification. By policy and outcome, we compared policy effects across studies and across racial/ethnic groups using two different ways to express effect sizes: incidence rate ratios (IRRs) and rate differences. Of 182 studies that used quasi-experimental methods to evaluate firearm policy effects, only 15 estimated policy effects differentiated by race or ethnicity. These 15 eligible studies provided 57 separate policy effect comparisons across race/ethnicity, 51 of which evaluated interpersonal violence. In IRR terms, there was little consistent evidence that policies produced significantly different effects for different racial/ethnic groups. However, because of different baseline homicide rates, similar relative effects for some policies (e.g., universal background checks) translated into significantly greater absolute differences in homicide rates among Black compared to white victims.

Conclusions

The current literature does not support strong conclusions about whether state firearm policies differentially benefit or harm particular racial/ethnic groups. This largely reflects limited attention to these questions in the literature and challenges with detecting such effects given existing data availability and statistical power. Findings also emphasize the need for additional rigorous research that adopts a more explicit focus on testing for racial differences in firearm policy effects and that assesses the quality of race/ethnicity information in firearm injury and crime datasets.

Inj Epidemiol. 2023; 10: 67.

By Ye Liu, Michael Siegel, Bisakha Sen 

Introduction: Firearm injury is a major U.S. public health concern. This study aims to evaluate whether the relationship between state firearm laws and state firearm deaths are affected by comparatively lenient firearm laws in neighboring states.

Methods: This observational study used 2000‒2017 data on firearm deaths and firearm laws of the 48 contiguous states of the U.S. (Alaska, Hawaii, and the District of Columbia excluded). The associations among state firearm deaths, state firearm laws, and presence of neighboring states with more lenient laws were analyzed using negative binomial regression models with state- and year-fixed effects. Analyses were conducted in 2019‒2020.

Results: There were 578,022 firearm deaths of all intents during the study period or 11.1 firearm deaths (IQR=8.5-14.0) per 100,000 population. The presence of more state firearm laws was associated with decreased firearm deaths (incident rate ratio=0.991, 95% CI=0.987, 0.996). However, weaker firearm laws in neighboring states correlated with more firearm deaths within a state (incident rate ratio=1.016, 95% CI=1.004, 1.028). Failing to account for weaker laws in neighboring states led to the underestimation of the impact of 1 additional law on state's own firearm deaths (incident rate ratio=0.994, 95% CI=0.989, 0.998 vs 0.991, 95% CI=0.987, 0.996) by approximately 20%.

American Journal of Preventive Medicine: 59(5): 648-657, 2020.

By Peter Andrew Gregory

This dissertation analyzes the relationships between four state gun laws—universal background checks, waiting periods, may-issue permitting, and violent misdemeanor prohibitions—and firearm homicide and suicide rates among Blacks and Whites in the United States. Using eighteen years of publicly available data, the study examined relationships employing a generalized difference-in-difference linear regression model with fixed effects for states and years. The results indicate that state gun laws in the United States frequently affect mortality rates among Blacks and Whites in different ways. Waiting periods, for example, are associated with large reductions in firearm homicide rates among Blacks but not Whites; may-issue permitting is associated with moderate reductions in firearm homicide rates among Whites but not among Blacks. The study also identifies several statistically significant interactive effects between gun laws and factors such as poverty, police presence, and the density of federally licensed firearm dealers. The dissertation concludes by discussing the value of these findings for informing both public policy and scholarly research in policy analysis and public administration. Most importantly, I argue that policymakers and gun violence researchers must increase their efforts to frame and analyze gun violence in the United States through the lens of social equity.

Blacksburg, VA: Virginia Polytechnic Institute and State University, 2022, 164p.