The Impact of State Firearm Laws on Homicide Rates in Suburban and Rural Areas Compared to Large Cities in the United States, 1991-2016.

PURPOSE: This article aims to examine whether state firearm laws impact homicide rates differently in suburban and rural areas compared to large cities in the United States. METHODS: We analyzed serial, cross-sectional data for the 26-year period 1991-2016 using a panel design. We examined the relationship between 6 specific state firearm laws and homicide rates in large cities (those with greater than 100,000 people in 1990) and in all geographic areas outside of these cities. Using a city-level fixed effects negative binomial regression, we modeled the number of homicides as a function of state firearm laws, while controlling for time fixed effects and time-varying state- and city-level sociodemographic factors. FINDINGS: Two policies-universal background checks and "may issue" laws that required a heightened showing of suitability for concealed carry-were associated with lower firearm homicide rates in large cities but were not associated with firearm homicide rates in suburban and rural areas. In contrast, laws that prohibited gun possession by people convicted of a violent misdemeanor were associated with lower firearm homicide rates in suburban and rural areas, but were not associated with firearm homicide rates in large cities. Permit requirements were associated with lower firearm homicide rates in both large cities and suburban and rural areas. CONCLUSIONS: This article provides the first evidence that state firearm laws may have a differential impact on firearm homicide rates in suburban and rural areas compared to urban areas in the United States.

The Impact of State Firearm Laws on Homicide Rates among Black and White Populations in the United States, 1991-2016.

This study aimed to investigate the potential differential effects of state-level firearm laws on black and white populations. Using a panel design, authors examined the relationship between state firearm laws and homicide victimization rates among white people and black people in 39 states during the period between 1991 and 2016. Authors modeled homicide rates using linear regression with year and state fixed effects and controlled for a range of time-varying, state-level factors. Results showed that universal background check laws and permit requirement laws were associated with lower homicide rates among both white and black populations, and "shall issue" laws were associated with higher homicide rates among both white and black populations. Laws that prohibit firearm possession among people convicted of a violent misdemeanor or require relinquishment of firearms by people with a domestic violence restraining order were associated with lower black homicide rates, but not with white homicide rates. Author identification of heterogeneity in the associations between state firearm laws and homicide rates among different racial groups has implications for reducing racial health disparities.

The Role of Racial Residential Segregation in Black-White Disparities in Firearm Homicide at the State Level in the United States, 1991-2015.

OBJECTIVE: To investigate the relationship between racial residential segregation and differences in Black-White disparities in overall firearm homicides across U.S states. METHODS: Using a linear regression, we evaluated the relationship between racial residential segregation, as measured by the index of dissimilarity, and the Black-White firearm homicide disparity ratio in 32 states over the period 1991-2015. To account for clustering of observations within states, we used a generalized estimating equations approach. RESULTS: After controlling for measures of White and Black deprivation, multivariate analysis showed that racial segregation was positively associated with the Black-White firearm homicide disparity. For each 10-point increase in the index of dissimilarity, the ratio of Black to White firearm homicide rates in a state increased by 39%. After controlling for levels of White and Black deprivation, racial segregation remained negatively associated with White firearm homicide rates and positively associated with Black firearm homicide rates. CONCLUSIONS: These findings suggest that racial segregation may increase the disparity in firearm homicide between the Black and White population.

State Firearm Laws and Interstate Transfer of Guns in the USA, 2006-2016.

In a cross-sectional, panel study, we examined the relationship between state firearm laws and the extent of interstate transfer of guns, as measured by the percentage of crime guns recovered in a state and traced to an in-state source (as opposed to guns recovered in a state and traced to an out-of-state source). We used 2006-2016 data on state firearm laws obtained from a search of selected state statutes and 2006-2016 crime gun trace data from the Bureau of Alcohol, Tobacco, Firearms, and Explosives. We examined the relationship between state firearm laws and interstate transfer of guns using annual data from all 50 states during the period 2006-2016 and employing a two-way fixed effects model. The primary outcome variable was the percentage of crime guns recovered in a state that could be traced to an original point of purchase within that state as opposed to another state. The main exposure variables were eight specific state firearm laws pertaining to dealer licensing, sales restrictions, background checks, registration, prohibitors for firearm purchase, and straw purchase of guns. Four laws were independently associated with a significantly lower percentage of in-state guns: a waiting period for handgun purchase, permits required for firearm purchase, prohibition of firearm possession by people convicted of a violent misdemeanor, and a requirement for relinquishment of firearms when a person becomes disqualified from owning them. States with a higher number of gun laws had a lower percentage of traced guns to in-state dealers, with each increase of one in the total number of laws associated with a decrease of 1.6 percentage points in the proportion of recovered guns that were traced to an in-state as opposed to an out-of-state source. Based on an examination of the movement patterns of guns across states, the overall observed pattern of gun flow was out of states with weak gun laws and into states with strong gun laws. These findings indicate that certain state firearm laws are associated with a lower percentage of recovered crime guns being traced to an in-state source, suggesting reduced access to guns in states with those laws.