Stand Your Ground: Policy and Trends in Firearm-Related Justifiable Homicide and Homicide in the US.

Background: In recent years, several states have enacted Stand Your Ground (SYG) legislation intended to deter crime. To date, the impact of these laws on justifiable homicide (JH) and homicide (HOM) is unknown. This study was designed to compare JH and HOM rates (JHR, HR) before and after enactment of SYG laws and in states with and without (NoSYG) such legislation.

Study Design: This was a retrospective analysis of justifiable homicide and homicide using 3 United States datasets from 2000 to 2017. Descriptive statistics and univariate linear regressions were used to evaluate the association of SYG laws and JH and HOM in the United States.

Results: There were 4,594 incidents of JH and 214,630 incidents of HOM in the United States between 2000 and 2017. Stand Your Ground states accounted for most JH and HOM incidents 3,184 (69%) and 116,511 (54%), respectively. Stand Your Ground states had higher JH and HOM rates than NoSYG states (0.126 vs 0.047 and 4.663 vs 3.301 per 100,000 population, respectively; p < 0.001). Comparing periods pre- (2000 to 2004) and post-SYG (2005 to 2017) law enactment, SYG vs NoSYG states had increased JH rates of 54.9% vs 20.4%, respectively (p < 0.001); HOM rates increased 10.8% in SYG states and decreased 2.3% in NoSYG states (p < 0.001).

Conclusions: Stand Your Ground states had significantly higher JH and HOM rates and significantly greater increases in JH and HOM rates pre- vs post-SYG law enactment compared with NoSYG states. These results raise questions about the potential adverse consequences of policies such as the SYG law in the US.