We Wanted to Know Whether Fewer Guns Lead to Fewer Suicides. Here’s What We Found.

Murder, theft, and other wickedness.
Dec. 12 2013 11:30 PM

It’s Simple: Fewer Guns, Fewer Suicides

Two scientists explore a decade of data to find the tie between gun ownership and suicide in America.

Man examining handgun at his home, Westminster, Colorado.
The relationship between guns and suicide is easier to study than guns and homicide.

Photo by Michael Smith/Getty Images

In the year since Adam Lanza used a Bushmaster rifle to gun down 20 children in Newtown, Conn., the discourse on gun control has focused on mass shootings and homicides. That’s not surprising: Terrible events dominate the cable news cycle, and murders get reported every day in our nation’s newspapers. But if we want to talk about the effects of guns, we should remember this: In a typical year, suicides outnumber homicides by 3 to 1 and a majority of suicides are by firearm. Suicides come in ones and twos, here and there; they rarely make the national news, and when they are reported at all they are veiled in euphemism (“He died suddenly”). Suicides go so underreported that Slate’s Gun Deaths Project, which collects data from news articles and other online sources, categorizes only roughly one-tenth of the reported deaths as suicides.

The national conversation about guns, and about gun control, should include the relationship between guns and suicide. We recently analyzed a decade’s worth of data on guns and suicides in the United States and we found that the relationship is clear: more guns, more suicides.

Suicide is neglected compared with the large quantity of research on the relationship between homicides and guns, a relationship which remains controversial because it’s difficult to demonstrate causality. Places with lots of guns may have high homicide rates, but is this because guns cause homicide or because homicides cause people to buy guns? Or could a third factor—say, a general lack of social trust or high violence in a region—be causing both homicides and gun possession? The relationship between suicides and guns is much easier to tackle because it’s unlikely that an increase in the number of suicides in a community would cause an increase in local gun ownership.

So in a new paper published in the International Review of Law and Economics, we studied the relationship between guns and suicide in the U.S. from 2000 to 2009. Using five measures of gun ownership and controlling for other factors associated with suicide, such as mental illness, we consistently found that each 1 percentage-point increase in household gun ownership rates leads to between 0.5 and 0.9 percent more suicides. Or, to put it the other way, a percentage-point decrease in household gun ownership leads to between 0.5 and 0.9 percent fewer suicides.

Are the people not killing themselves with guns simply committing suicide by other means? Some are—but not all. While reduced household gun ownership did lead to more suicides by other means, suicides went down overall. That’s because contrary to the “folk wisdom” that people who want to commit suicide will always find a way to get the job done, suicides are not inevitable. Suicides are often impulsive decisions, and guns require less forethought than other means of suicide—and they’re also deadlier.

Our research had to overcome the fact that no one knows with great precision how many guns there are in America, how many households own a gun, how gun ownership varies demographically and geographically, what types of guns there are, or how guns are used. In part that’s because in 1996, Congress banned the CDC from funding any research to "advocate or promote gun control." That’s not a ban on gun research, technically, but after Congress extended the wording and expanded the ban to other agencies, it had enough of a chilling effect to reduce CDC funding for gun violence research from $2.5 million per year in the early 1990s to just $100,000 in recent years.

But don’t take our critique of bans on government-funded research as a plea for more funding for our research. We would be satisfied if the CDC and other government agencies such as the Bureau of Justice Statistics were simply allowed to collect more and better data on guns, homicide and suicide. The CDC’s National Violent Death Reporting System, for example, still covers only 18 states. President Obama lifted some of the restrictions on the CDC earlier this year, so we are cautiously optimistic about the prospects for future research. (Gun advocates and supporters of Second Amendment rights shouldn’t assume that more research simply means more arguments against guns. We are eager, for example, to see more studies on the defensive use of guns, a phenomenon about which there is currently very little trustworthy data. Moreover, better research might find ways of reducing gun violence without violating Second Amendment rights. Indeed, reducing gun violence could be one of the best ways of reducing the demand for gun control.)

Despite challenges presented by the data, our findings appear robust and are consistent with a series of “natural experiments” from around the world. For example, following the 1996 killing of 35 people in Port Arthur, Australia, a strong movement for gun control developed in Australia. States and territories made uniform and more stringent regulations for the possession of firearms, and instituted a buy-back of the newly illegal guns, most of which were rifles and shotguns. As Andrew Leigh and Christine Neill determined in a paper published in the American Law and Economics Review, these changes resulted in a reduction of the country’s firearm stock by 20 percent, or more than 650,000 firearms, and evidence suggests that it nearly halved the share of Australian households with one or more firearms. The effect of this reduction was an 80 percent fall in suicides by firearm, concentrated in regions with the biggest drop in firearms. Meanwhile there was little sign of any lasting rise in non-firearm suicides.

Suicide is a leading cause of death among adolescents and young adults, and limiting access to guns during those formative, sometimes unsteady years can have a real effect on suicides. In Israel most 18- to 21-year-olds are drafted into the Israeli Defense Forces and provided with military training—and weapons. Suicide among young IDF members is a serious problem. In an attempt to reduce suicides, the IDF tried a new policy in 2005, prohibiting most soldiers from bringing their weapons home over the weekends. Dr. Gad Lubin, the chief mental health officer for the IDF, and his co-authors estimate that this simple change reduced the total suicide rate among young IDF members by a stunning 40 percent. It’s worth noting that even though you might think that soldiers home for the weekend could easily delay suicide by a day or two, the authors did not find an increase in suicide rates during the weekdays. These results are consistent with interviews with near-fatal suicide survivors, who often say their decision was spontaneous and who typically go on to live long lives.

If more guns lead to more suicides, should we ban guns as Australia did? Not necessarily. We find that a 1 percentage-point increase in the household gun-ownership rate increases suicides by at most 0.9 percent. There are 114 million households in the U.S., so a 1 percentage-point increase in ownership means approximately 1.1 million more households with guns. Since there are relatively few suicides, this translates into 345 more suicides, at most. In this sense, guns are relatively benign. Most guns are never involved in a suicide or a homicide.

But lives have great value. Government agencies such as the EPA value a statistical life at around $8.4 million (2006 dollars updated to 2012). Calculating the value of life is probably something only an economist would ever think to do, but it's a useful exercise. When evaluating everything from how much to spend on straightening roads or researching cancer drugs, we need to have some idea, however crude, of the value of lives lost and saved. At $8.4 million each the value of 345 lost lives is almost $3 billion. Considering the value of life tells us that the true price of guns is higher than the monetary price by at least $2,635, the amount needed to be able to compensate for the expected loss of life. At that price, fewer people should want to buy guns.

Guns in the home are a risk factor for suicide, and the risk is especially great if there is a depressed adolescent living at home. Unfortunately, people don’t always weigh risks carefully. In one study, even when strongly recommended by mental health professionals to do so, most parents of a depressed adolescent didn’t remove their guns from their home. It’s also disturbing that guns were least likely to be removed when the father of the depressed adolescent had a drinking or drug problem of his own.

Suicide gets less attention, less funding, and less concern than many other kinds of deaths. San Francisco spent $26.5 million installing a new median barrier on the Golden Gate Bridge even though there hasn't been a fatal head-on car crash on the bridge in 12 years. But no funds have been spent on a system to help prevent suicides, despite the fact that 10 people died committing suicide on the bridge in August of 2013 alone. It’s true, of course, that unlike homicides or accidents, suicide is a choice, but it’s a choice often made under the duress of crisis or depression. Moreover, suicide is not chosen by the friends, siblings, children, spouse, or parents of the person who commits suicide. Losing a loved one to suicide is a traumatic and painful experience. Suicide and its relationship to mental health, social isolation, and firearm access deserve our full attention and concern.

Justin Briggs is a graduate student at George Mason University.

Alex Tabarrok is Bartley J. Madden Chair and professor of economics at George Mason University.