On February 14, 2018, America suffered another mass shooting. Seventeen people were killed and fourteen wounded by a lone gunman and former student at Marjory Stoneman Douglas High School in Parkland, Florida. After the initial horror of the shooting passed, politicians turned, as they usually do, to offering their favored policy solutions for reducing gun violence in America. In general, Republicans, like President Donald Trump, focused on the role of mental illness, while Democrats, such as former President Barack Obama, called for stricter gun control laws.
We tested relative effectiveness of these two approaches by investigating the effects of relatively strong gun control laws against greater access to mental health services for those in need on the rate of gun deaths for each state. And we found these two solutions are not equally effective.
There's an intuitive rationale to each approach. Proponents of gun control laws argue that restrictions on guns can be targeted to keep them out of the hands of those most likely to be homicidal or suicidal, and that imposing additional restrictions, such as limiting the type of guns allowed (e.g., banning assault-style weapons) may make shootings less deadly.
Those in favor of a mental health solution argue that there is a link between mental illness and gun violence, and that mental illness can often be managed through care from medical professionals (e.g., psychotherapy and/or drug therapy), preventing people from becoming violent toward themselves or others.
Finally, some push a cross-over argument that a combination of both approaches may be best since policymakers can target gun restrictions at those with serious mental illness, while at the same time providing greater access to treatment for those in need so they don’t turn to violence in the first place.
In our forthcoming paper from Policy Studies Journal, we used statistical analysis to leverage the variation in gun policy and access to mental health services between states using data from the Brady Campaign to Prevent Gun Violence and Mental Health America. This approach allowed us to examine which policies most effectively address gun violence by comparing how different policies relate to the rate of gun deaths in each state.
We found that relatively strict gun control laws are correlated with fewer gun deaths by state after controlling for various other relevant factors. At the same time, a relatively high rate of access to mental health services for those who report needing them does not appear to have an effect on the number of people dying from guns. We did, however, find support for the combination approach. States with better access to mental health services and stricter gun control laws suffer fewer gun deaths.
When breaking the results down by suicide and non-suicide deaths (i.e., homicides and accidental shootings), we find that for non-suicides, the results are broadly similar. That is, relatively strict gun control laws, and a combination of strict gun control and a relatively high rate of access to mental health services, are correlated with fewer homicides and accidental shooting deaths.
However, when we looked solely at suicides committed with a gun, we found that only strict gun control laws are correlated with fewer gun-related suicides, not greater access to mental health services, and not the combination approach. We theorized that is because individuals have to be committed to a mental institution or declared mentally incompetent in order for their guns to be legally taken away due to mental illness. Those with the rare mental illness that may make them more likely to commit violent crimes against others (e.g., schizophrenia), the primary factor that would make one more likely to be committed or declared mentally incompetent, are also then more likely to have their guns taken away than those who are suicidal.
What does all of this mean for addressing the problem of gun violence in America? If policymakers are interested in reducing the number of gun-related deaths in the United States, they have a clear path forward. Stricter gun control laws consistently result in fewer gun deaths whether these are homicides, suicides or accidental shootings. At the same time, providing greater access to mental health services, while perhaps not as effective at reducing suicides committed with a gun as we would hope, would still help reduce the rate of gun-related homicides if used in tandem with strict gun control laws.
Through such an approach, America has the potential to reduce its rate of gun deaths and prevent future shootings. That being said, it is clear that simply possessing evidence on the effectiveness of gun violence solutions will not by itself be enough to avert the next tragedy. What is needed next is the political courage to act on the evidence presented here and elsewhere that the most effective solution to gun violence is in fact an approach that focuses on guns.
Jonathan Spiegler is a doctoral student in the Department of Political Science at Michigan State University. Jacob Smith is a Ph.D. candidate in the Department of Political Science at the University of North Carolina at Chapel Hill.