Number of firearm laws significantly predicted suicide and homicide rates, Rutgers study finds

States with stricter firearms laws reported lower suicide and homicide rates, according to a Rutgers study.

The study, conducted by the New Jersey Gun Violence Research Center, the Rutgers School of Public Health, the Rutgers University–Newark Department of Psychology, the Rutgers School of Criminal Justice, the Rutgers New Jersey Medical School and the Rutgers–Newark Department of Social Work, was published in the Journal of Public Health and examined the association between firearm laws and suicide and homicide rates. 

Firearm violence is a major public health concern in the United States, with firearm suicide and homicide accounting for the majority of gun deaths. In 2017, 66,683 people died by suicide and homicide with a majority of the deaths resulting from a firearm: 48 percent for suicide and 74 percent for homicide. 

Using the State Firearm Law Database, the Rutgers researchers compared suicide and homicide rates across the United States from 1991 to 2017 with the number of firearm laws in each state.  The study found that even with several factors, such as unemployment and overall gun ownership rates, taken into account, the total number of firearm laws in a state was a significant predictor of suicide and homicide rates.

“As states’ strictness increased, their suicide and homicide rates decreased,” said lead author John F. Gunn III, a postdoctoral researcher at the Rutgers School of Public Health and New Jersey Gun Violence Research Center.

The researchers, who were the first to focus on the impact of the total number of firearms regulations in each state, utilized a general index of states’ overall approach to firearms regulation by aggregating the total number of gun laws. This index broadly defined states as restrictive or lenient towards firearms.

“With close to 40, 000 deaths annually from firearm violence, regulations that can limit access to firearms appear to reduce state-level mortality,” says senior study author Bernadette Hohl, an assistant professor at Rutgers School of Public Health. “Evidence-based implementation of firearm regulations across the whole of the United States has the potential to significantly reduce the toll of firearm violence.”

Previous research supports associations between state suicide and homicide rates and specific gun laws, such as waiting periods and universal background checks, with most work finding that the presence of specific firearm laws is associated with reductions in gun mortality.

Future research is required to continue to holistically examine the relationship between firearm laws and suicide and homicide rates. “Assessing the implications of law changes, regulation enforcement and if there is a correlation with violent crime decline will be necessary,” Gunn said.