State-Level Firearm Laws and Firearm Homicide in US Cities: Heterogenous Associations by City Characteristics.

Despite well-studied associations of state firearm laws with lower state- and county-level firearm homicide, there is a shortage of studies investigating differences in the effects of distinct state firearm law categories on various cities within the same state using identical methods. We examined associations of 5 categories of state firearm laws-pertaining to buyers, dealers, domestic violence, gun type/trafficking, and possession-with city-level firearm homicide, and then tested differential associations by city characteristics. City-level panel data on firearm homicide cases of 78 major cities from 2010 to 2020 was assessed from the Centers for Disease Control and Prevention's National Vital Statistics System. We modeled log-transformed firearm homicide rates as a function of firearm law scores, city, state, and year fixed effects, along with time-varying city-level confounders. We considered effect measure modification by poverty, unemployment, vacant housing, and income inequality. A one z-score increase in state gun type/trafficking, possession, and dealer law scores was associated with 25% (95% confidence interval [CI]:-0.37,-0.1), 19% (95% CI:-0.29,-0.07), and 17% (95% CI:-0.28, -0.4) lower firearm homicide rates, respectively. Protective associations were less pronounced in cities with high unemployment and high housing vacancy, but more pronounced in cities with high income inequality. In large US cities, state-level gun type/trafficking, possession, and dealer laws were associated with lower firearm homicide rates, but buyers and domestic violence laws were not. State firearm laws may have differential effects on firearm homicides based on city characteristics, and city-wide policies to enhance socioeconomic drivers may add benefits of firearm laws.

Effects of Comprehensive Background-Check Policies on Firearm Fatalities in 4 States.

Despite promising results from individual-level studies, state-level studies of the effectiveness of comprehensive background-check (CBC) policies in reducing firearm fatalities have yielded null results in multiple states. These prior studies focused on CBC laws adopted in the 1990s, when record keeping was far less complete. We estimated the effect of the implementation of CBC policies on state-level firearm homicide and suicide rates in states implementing CBC policies from 2013 to 2015 (Colorado, Delaware, Oregon, and Washington). We compared age-adjusted firearm homicide and suicide rates, measured annually from 15 years prior to policy implementation until 2019, in each treated state to rates in control groups constructed using the synthetic control group method. Differences in firearm homicide rates for Colorado, Oregon, and Washington post treatment were all small (0.09 to 0.18 per 100,000 residents per year) and not well distinguished from natural variation. Oregon had on average 0.80 per 100,000 fewer firearm suicides per year than did synthetic Oregon post treatment. However, these results were inconsistent across modeling approaches and not well distinguished from natural variation. Our models produced poor fit for Delaware. Coupled with previous null results from Indiana, California, Maryland, Pennsylvania, and Tennessee, the present results suggest that extending background check requirements to private transfers alone and implementing these policies as is currently done is not sufficient to achieve significant state-level reductions in firearm fatalities.

Restrictive Firearm Laws and Firearm-Related Suicide.

BACKGROUND: There were 23,854 suicides by firearms in 2017 in the US, accounting for 60% of all gun deaths. Studying firearm-related mortalities is vital for reducing preventable gun deaths. This study aims to determine the association between state-level presence of restrictive firearm laws and suicide rates with firearms. STUDY DESIGN: This ecological study used data from the CDC Wide-Ranging Online Data for Epidemiologic Research on decedents older than 18 years who died from intentional self-harm with firearms between 2009 and 2018. Exposures of interest were state-level restrictive firearm laws: background checks on private sales, mandatory waiting periods, and prohibited possession for domestic violence restraining orders or mental health red flags. Outcomes were rates of suicide with firearms per 100,000 persons over the 10-year period within each state. Welch's t -tests compared mean mortality rates in exposed and unexposed states. RESULTS: There were 208,621 deaths from intentional self-harm with firearms from 2009 to 2018. States with background checks, mandatory waiting periods, and prohibited possession were associated with lower suicide rates for all firearm types compared with states without these laws (p < 0.05). Only states with background checks and mandatory waiting periods were associated with lower suicide rates by handguns and large firearms (p < 0.05). CONCLUSION: Background checks and mandatory waiting periods correlated with fewer suicides by all firearms and specific firearm types. This reduction could be due to firearm laws directly preventing people from accessing guns or existing concurrently with other suicide prevention measures. More research should be directed to understanding how firearm laws can help reduce suicide rates.

Child Access Prevention Laws and Non-Hispanic Black Youth Firearm Mortality.

Firearm injuries are the leading cause of death for youths 19 and younger in general and the third leading cause of death for non-Hispanic Black youths. Child Access Prevention (CAP) laws have been explored concerning their impact on firearm mortality reduction among heterogenous groups of youth, but not specifically among non-Hispanic Black youths. We analyzed data related to non-Hispanic Black youth firearm mortality, non-Hispanic Black poverty rates, firearm dealer density, and CAP laws for each state to ascertain the impact of CAP laws from 2015 to 2019. During the study period, a total of 6778 non-Hispanic Black youths died due to firearm trauma with the leading causes of death being homicides (85.8%); mostly seen among males (96%), and in the South (53.2%). When compared by CAP laws, the states with the strongest laws had statistically significantly lower rates of firearm mortality than states with the weakest laws. After adjusting for state poverty and firearm dealer density, the differences were not statistically significant but still, stronger CAP laws were associated with lower rates of firearm mortality among non-Hispanic Black youth. CAP laws alone can have a modest impact on non-Hispanic Black youth firearm mortality. To adequately reduce firearm mortality among non-Hispanic Black youths, the state and local governments should, along with CAP laws, enact policies to reduce poverty, crime, access to firearms by criminals, and neighborhood dysfunction among non-Hispanic Black communities.

Regulating Assault Weapons and Large-Capacity Magazines for Ammunition.

This Viewpoint discusses the history and current status of assault weapons bans in the US, provides evidence of the potential effectiveness of a US ban and information regarding the Australian ban, and explores potential next steps.

State Firearm Laws and Firearm-Related Mortality and Morbidity.

This Viewpoint highlights the challenges to passing federal legislation that limits gun ownership and accessibility and summarizes some of the state laws used to successfully lower rates of firearm-related death and injury.

The Supreme Court Expands Second Amendment Rights as the Nation Experiences Historic Levels of Firearms Violence.

This Viewpoint discusses the recent Supreme Court decision declaring a broad right to carry firearms in public and offers a public health strategy for firearms safety laws.

Examining the Impact of Firearm Safety Laws on Suicides.

This Medical News feature discusses what's known about the impact of firearm safety laws on suicide rates.

Analysis of "Stand Your Ground" Self-defense Laws and Statewide Rates of Homicides and Firearm Homicides.

Importance: Most US states have amended self-defense laws to enhance legal immunities for individuals using deadly force in public. Despite concerns that "stand your ground" (SYG) laws unnecessarily encourage the use of deadly violence, their impact on violent deaths and how this varies across states and demographic groups remains unclear. Objective: To evaluate the association of SYG laws with homicide and firearm homicide, nationally and by state, while considering variation by the race, age, and sex of individuals who died by homicide. Design, Setting, and Participants: This cohort study used a controlled, multiple-baseline and -location interrupted time series design, using natural variation in the timings and locations of SYG laws to assess associations. Changes in homicide and firearm homicide were modeled using Poisson regression analyses within a generalized additive model framework. Analyses included all US states that enacted SYG laws between 2000 and 2016 and states that did not have SYG laws enacted during the full study period, 1999 to 2017. Data were analyzed from November 2019 to December 2020. Exposures: SYG self-defense laws enacted by statute between January 1, 2000, to December 31, 2016. Main Outcomes and Measures: The main outcomes were statewide monthly rates of homicide and firearm-related homicide (per 100 000 persons) from January 1, 1999, to December 31, 2017, grouped by characteristics (ie, race, age, sex) of individuals who died by homicide. Results: Forty-one states were analyzed, including 23 states that enacted SYG laws during the study period and 18 states that did not have SYG laws, with 248 358 homicides (43.7% individuals aged 20-34 years; 77.9% men and 22.1% women), including 170 659 firearm homicides. SYG laws were associated with a mean national increase of 7.8% in monthly homicide rates (incidence rate ratio [IRR],1.08; 95% CI, 1.04-1.12; P < .001) and 8.0% in monthly firearm homicide rates (IRR, 1.08; 95% CI, 1.03-1.13; P = .002). SYG laws were not associated with changes in the negative controls of suicide (IRR, 0.99; 95% CI, 0.98-1.01) or firearm suicide (IRR, 1.00; 95% CI, 0.98-1.02). Increases in violent deaths varied across states, with the largest increases (16.2% to 33.5%) clustering in the South (eg, Alabama, Florida, Georgia, Louisiana). There were no differential associations of SYG laws by demographic group. Conclusions and Relevance: These findings suggest that adoption of SYG laws across the US was associated with increases in violent deaths, deaths that could potentially have been avoided.

Assessment of Reasons for Ownership and Attitudes About Policies Among Firearm Owners With and Without Children.

Importance: Given the dangers that firearms in the home pose to children, it is critical to engage parents in effective firearm safety counseling. This requires a broader understanding of how the presence of children in the home is associated with motivations surrounding gun ownership. Objective: To examine the association of having children in the home and gun owners' attitudes and beliefs. Design, Setting, and Participants: This cross-sectional survey study analyzed data from the National Lawful Use of Guns Survey conducted in 2019. A representative sample of 3698 adult gun owners nationwide were randomly invited to participate, with a 56.5% survey response rate. Survey responses were weighted to account for survey nonresponse and selection bias, and comparison groups were matched by age. Statistical analysis was performed in 2020. Main Outcomes and Measures: Reasons for gun ownership, symbolic meaning of guns, and attitudes toward gun policies. Results: Of the 2086 respondents, 383 (18.4%) had children in the home, 68.7% (95% CI, 66.4%-71.0%) were male, 8.2% (95% CI, 6.8%-9.7%) were Black, 76.3% (95% CI, 73.8%-78.6%) were White, 79.4% (95% CI, 77.5%-81.2%) were living in metropolitan areas, 51.3% (95% CI, 48.9%-53.8%) identified as Republican; 34.7% (95% CI, 32.6%-36.9%) were aged 60 years or older. Despite the majority of respondents feeling safe in their local communities (respondents with children: 93.4% [95% CI,: 89.3%-96.0%]; without children: 88.9% [95% CI, 87.0%- 90.6%]), 92.3% (95% CI, 87.0%-95.6%) of respondents with children stated the primary reason for gun ownership was to protect their family, compared with 68.6% (95% CI, 65.2%-71.8%) of respondents without children. On logistic regression analysis, having children in the home remained an independent factor associated with reasons for gun ownership. Gun owners with children were more likely than those without children to feel that guns make them feel more valuable to their family (23.5% [95% CI, 18.9%-28.8%] vs 17.0% [95% CI, 15.0%-19.2%]). Among those with children, 35.2% (95% CI, 30.0%-40.8%) believed gun laws should be more strict compared with 40.7% (95% CI, 38.1%- 43.3%) of those without children. Conclusions and Relevance: These findings suggest that acknowledging parental motivations for gun ownership is a pivotal component of educational efforts toward firearm injury prevention. These findings can guide clinicians to engage in effective individual counseling and community level efforts to reduce pediatric gun injuries.

State firearm laws and nonfatal firearm injury-related inpatient hospitalizations: A nationwide panel study.

BACKGROUND: Firearm injury remains a major cause of morbidity and mortality in the United States. Because of prior lack of comprehensive data sources, there is a paucity of literature on nonfatal firearm injury. Associations have previously been shown between state-level firearm laws and firearm fatalities, but few studies have examined the effects of these laws on nonfatal firearm hospitalization rates. Our objective was to examine the relationship between state firearm laws and firearm injury-related hospitalization rates across all 50 states over a 17-year period. METHODS: In this panel study design, we used fixed effects multivariate regression models to analyze the relationship between 12 laws and firearm state-level injury-related hospitalization rates from 2000 to 2016 using the RAND Corporation Inpatient Hospitalizations for Firearm Injury Database. We used difference-in-differences to determine the impact of law passage in a given state compared with those states without the law, controlling for state-level covariates. The main outcome measure was the change in annual firearm injury-related inpatient hospitalization rates after passage or repeal of a state-level firearm law. RESULTS: Examining each law individually, passage of violent misdemeanor, permitting, firearm removal from domestic violence offenders, and 10-round limit laws were associated with significant firearm injury-related hospitalization rate reductions. Examining multiple laws in the same model, passage of violent misdemeanor laws was associated with a 19.9% (confidence interval, 11.6%-27.4%) reduction, and removal of firearms from domestic violence offenders was associated with a 17.0% (confidence interval, 9.9%-23.6%) reduction in hospitalization rates. CONCLUSION: State laws related to preventing violent offenders from possessing firearms are associated with firearm injury-related hospitalization rate reductions. Given significant physical, mental, and social burdens of nonfatal firearm injury, determining the efficacy of firearm-related policy is critical to violence and injury prevention efforts. LEVEL OF EVIDENCE: Prognostic and Epidemiologic; Level IV.

The limitations of hospital and law enforcement databases in characterizing the epidemiology of firearm injury.

BACKGROUND: Current data on the epidemiology of firearm injury in the United States are incomplete. Common sources include hospital, law enforcement, consumer, and public health databases, but each database has limitations that exclude injury subgroups. By integrating hospital (inpatient and outpatient) and law enforcement databases, we hypothesized that a more accurate depiction of the totality of firearm injury in our region could be achieved. METHODS: We constructed a collaborative firearm injury database consisting of all patients admitted as inpatients to the regional level 1 trauma hospital (inpatient registry), patients treated and released from the emergency department (ED), and subjects encountering local law enforcement as a result of firearm injury in Jefferson County, Kentucky. Injuries recorded from January 1, 2016, to December 31, 2020, were analyzed. Outcomes, demographics, and injury detection rates from individual databases were compared with those of the combined collaborative database and compared using χ2 testing across databases. RESULTS: The inpatient registry (n = 1,441) and ED database (n = 1,109) were combined, resulting in 2,550 incidents in the hospital database. The law enforcement database consisted of 2,665 patient incidents, with 2,008 incidents in common with the hospital database and 657 unique incidents. The merged collaborative database consisted of 3,207 incidents. In comparison with the collaborative database, the inpatient, total hospital (inpatient and ED), and law enforcement databases failed to include 55%, 20%, and 17% of all injuries, respectively. The hospital captured nearly 94% of survivors but less than 40% of nonsurvivors. Law enforcement captured 93% of nonsurvivors but missed 20% of survivors. Mortality (11-26%) and injury incidence were markedly different across the databases. DISCUSSION: The utilization of trauma registry or law enforcement databases alone do not accurately reflect the epidemiology of firearm injury and may misrepresent areas in need of greater injury prevention efforts. LEVEL OF EVIDENCE: Epidemiological, level IV.