The Impact of Firearm Legislation on Firearm Deaths, 1991-2017.

Firearm violence is a major public health concern in the USA with firearm suicide and homicide accounting for the majority of gun deaths. The present work seeks to explore the role of firearm legislation in reducing suicide and homicide rates. Using the State Firearm Law Database (www.statefirearmlaws.org), suicide and homicide rates were compared across the 50 US states from 1991 to 2017. A firearm regulations index was computed to represent the total number of state firearm laws. Generalized estimating equations were used to explore population-level increases or decreases in firearm regulations and their association with state suicide and homicide rates after controlling for several state-level covariates. Even after accounting for several key covariates (US region; time; gun ownership; percent of the state population that was White, Black, below the poverty line and 25 years or older with a bachelor's degree; incarceration rate, unemployment rate and divorce rate), we found that firearm laws significantly predicted state firearm suicide and homicide rates. States with greater numbers of laws had reduced suicide and homicide rates compared with those with fewer laws. The present findings point to the role of firearm legislation in curbing rates of gun violence across the USA.