1. States with more gun control laws have lower levels of firearm homicide and firearm suicide

Using state data from 2007-2010, we found that states with more key firearm laws had fewer firearm homicides and fewer firearm suicides, after controlling for poverty, unemployment, education, race and non-firearm violence-related deaths.

Fleegher, Eric W; Lee, Lois K; Monuteaux, Michael C; Hemenway, David; Mannix, Rebekah. Firearm legislation and firearm-related fatalities in the United States. JAMA-Internal Medicine. 2013; 173:732-40.

2. “Shall issue” laws have no significant effect on the overall homicide rate

We analyzed the effect on homicide of changes in state-level gun carrying laws using pooled cross-sectional time-series data for 50 states from 1979-1998. There was no statistically significant association between changes in concealed carry laws and state homicide rates. The finding was consistent across a variety of models.

Hepburn, Lisa; Miller, Matthew; Azrael, Deborah; Hemenway, David. The effect of nondiscretionary concealed weapon carrying laws on homicide. Journal of Trauma. 2004; 56:676-681.

3. Child access prevention laws may reduce unintentional child firearm fatalities

We analyzed the effect on unintentional firearm fatalities to children of child access prevention (CAP) laws, which allow a firearm owner to be charged with a crime if a child gains access to an unsecured firearm, using pooled cross-sectional time series data for 50 states from 1979 to 2000. We found that states that enacted CAP laws – with felony rather than misdemeanor penalties – experienced grater subsequent declines in the rate of unintentional firearm deaths for children age 0 to 14 years, compared to states not enacting CAP laws.

Hepburn, Lisa; Azrael, Deborah; Miller, Matthew; Hemenway, David. The effect of child access prevention laws on unintentional child firearm fatalities, 1979-2000. Journal of Trauma. 2006; 61:423-28.

4. Some gun policy evaluations are designed to ensure that no effect will be found

This article on statistics describes the limitations of studies that claim no effect of gun shows and no effect of the Australian gun buyback.

Hemenway, David. How to find nothing. Journal of Public Health Policy. 2009; 30:260-68.

5. Results of a flawed study results should not affect policy

This paper highlights the serious flaws in a study that found no effect of gun shows on homicide or suicide.

Wintemute, Garen; Hemenway, David; Webster, Daniel; Pierce Glenn; Braga Anthony A. Gun shows and gun violence: Fatally flawed study. American Journal of Public Health. 2010;100;1856-60.

6. The Brady Bill has major limitations in scope, monitoring and enforcement

One section of this chapter discusses the three aspects of regulation: the rules, monitoring of those rules, and punishments if the rules are not complied with. The Brady bill is discussed as an example of a law with major deficiencies in all three aspects.

Hemenway, David. Public policy. In: Guohua Li and Susan P. Baker, eds. Injury Research: Theories, Methods and Approaches. New York: Springer, 2012.

7. States with strong gun laws have lower rates of firearm homicide and firearm suicide

We conducted a state-level ecological study for 2007-2010 and found that states with more firearm laws had lower rates of both gun homicide and gun suicide, even after controlling for race, poverty, unemployment, college education, population density, and non-firearm deaths.

Reviews by the Centers for Disease Control and the Institute of Medicine conclude that the evidence is not strong enough to determine whether or not firearm laws reduce lethal violence. This study provides evidence consistent with the hypothesis that firearm laws are effective in reducing homicide and suicide.

Fleegler EW, Lee LK, Monuteaux MC, Hemenway D, Mannix R. Firearm legislation and firearm-related fatalities in the United States. JAMA-Internal Medicine. 2013; 173:732-40.