Effects of State Gun Laws and Gun Ownership on Gun Violence

Do gun laws have an effect on gun violence?  This is one of the most debated questions related to gun policy and efforts to reform or tighten existing gun laws.  As a result, this topic has been researched extensively from everyone from medical researchers to epidemiologists, to public health experts, to economists.  The answer to the question is a resounding “yes.”  There is undoubtedly a relationship between laws and policies related to firearms and the frequency, rate, and lethality of gun violence.

Below are a number of academic research studies and publications related to the effect of state firearm laws and gun ownership on gun violence.

State Gun Laws and Pediatric Firearm-Related Mortality
Monika K. GoyalGia M. BadolatoShilpa J. PatelSabah F. IqbalKavita ParikhRobert McCarter
Pediatrics (2019)
Key findings: In this 5-year analysis, states with stricter gun laws and laws requiring universal background checks for firearm purchase had lower firearm-related pediatric mortality rates. These findings support the need for further investigation to understand the impact of firearm legislation on pediatric mortality.

State Gun Laws, Gun Ownership, and Mass Shootings in the US: Cross Sectional Time Series
Paul M Reeping, doctoral student, Magdalena Cerdá, associate professor, Bindu Kalesan, assistant professor, Douglas J Wiebe, professor, Sandro Galea, dean,   Charles C Branas, professor
British Medical Journal (2019)
Key findings: States with more permissive gun laws and greater gun ownership had higher rates of mass shootings, and a growing divide appears to be emerging between restrictive and permissive states.

Firearm Laws and Firearm Homicides
A Systematic Review
Lois K. Lee, MD, MPH; Eric W. Fleegler, MD, MPH; Caitlin Farrell, MD; Elorm Avakame, BS; Saranya Srinivasan, MD; David Hemenway, PhD; Michael C. Monuteaux, ScD
Journal of the American Medical Association (2017)
Key findings:
The strength of firearm legislation in general, and laws related to strengthening background checks and permit-to-purchase in particular, is associated with decreased firearm homicide rates. High-quality research is important to further evaluate the effectiveness of these laws.

State Intimate Partner Violence–Related Firearm Laws and Intimate Partner Homicide Rates in the United States, 1991 to 2015
Carolina Díez, BA; Rachel P. Kurland; Emily F. Rothman, ScD; Megan Bair-Merritt, MD, MSCE; Eric Fleegler, MD, MPH; Ziming Xuan, ScD, SM, MA; Sandro Galea, MD, DrPH, MPH; Craig S. Ross, PhD, MBA; Bindu Kalesan, PhD, MPH, MSc; Kristin A. Goss, PhD, MPP; Michael Siegel, MD, MPH
Annals of Internal Medicine (2017)
Key Findings
State laws that prohibit persons subject to intimate partner violence-related restraining orders from possessing firearms and also require them to relinquish firearms in their possession were associated with 9.7% lower total intimate partner homicide (IPH) rates (95% CI, 3.4% to 15.5% reduction) and 14.0% lower firearm-related IPH rates (CI, 5.1% to 22.0% reduction) than in states without these laws.

What Do We Know About the Association Between Firearm Legislation and Firearm-Related Injuries?
Julian Santaella-Tenorio, Magdalena Cerdá, Andrés Villaveces, Sandro Galea
Epidemiologic Review (2016)
Key findings:
Specific laws combining different types of firearm regulations are the best way to reduce deaths from gun violence. Some specific regulations – such as background checks – are the most effective. 

Firearm legislation and firearm mortality in the USA: a cross-sectional, state-level study
Dr Bindu Kalesan, PhD, Matthew E Mobily, MD, Olivia Keiser, PhD, Jeffrey A Fagan, PhD, Sandro Galea, MD
The Lancet (2016)
Key findings: Very few of the existing state-specific firearm laws are associated with reduced firearm mortality, and
this evidence underscores the importance of focusing on relevant and effective firearms legislation. Implementation of universal background checks for the purchase of firearms or ammunition, and firearm identification nationally could substantially reduce firearm mortality in the USA.

Firearm Prevalence and Homicides of Law Enforcement Officers in the United States
David I. Swedler PhD, MPH; Molly M. Simmons AB, Francesca Dominici PhD; David Hemenway PhD
American Journal of Public Health (2015)
Key findings: High public gun ownership is a risk for occupational mortality for law enforcement officers in the United States.

Firearm Legislation and Firearm-Related Fatalities in the United States
Eric W. Fleegler, MD, MPHLois K. Lee, MD, MPHMichael C. Monuteaux, ScD; et al
Journal of the American Medical Association (2013)
Key findings: A higher number of firearm laws in a state are associated with a lower rate of firearm fatalities in the state, overall and for suicides and homicides individually. As our study could not determine cause-and-effect relationships, further studies are necessary to define the nature of this association.