School Shootings Less Likely in States with Background Checks on Gun Purchases.

School shootings are less likely in US states with mandatory background checks on gun and ammunition purchases and with higher levels of spending on mental health services and public education, according to a new study led by researchers from the Schools of Public Health and Medicine.

Gun violence kills roughly 33,000 people a year and injures another 81,000. The number of school shootings is particularly high, with 154 incidents between 2013 and 2015, according to the study in the journal Injury Prevention.

The Sandy Hook Elementary School shooting in Connecticut in 2012, in which 20 children and six staff members were shot dead by a lone gunman, prompted much soul-searching about the possible factors involved, the authors noted, but to date, there has been little in the way of hard evidence to inform these discussions.

In a bid to address this, and in the absence of any official monitoring system, the researchers drew on a systematic analysis of media coverage of school shootings between 2013 and 2015 to see if the frequency of these incidents might be linked to particular state-level factors. These included: the presence or absence of mandatory background checks for all gun and ammunition purchases; the extent of gun ownership; mental health expenditures per capita; spending on public school education (K-12); and the proportion of people living in towns and cities.

On average, there was one school shooting every week over the course of the three years, and the number of incidents rose year to year—from 35 in 2013, to 55 in 2014, to 64 in 2015.

Thirty-nine states had at least one school shooting, while 11 had none: Alaska, Connecticut, Hawaii, New Hampshire, New Jersey, New York, North Dakota, Rhode Island, Vermont, West Virginia, and Wyoming.

Most states (34) in which school shootings occurred had fewer than 10 incidents, but Florida, Georgia, North Carolina, Tennessee, and Texas had 14, 15, 12, 10, and 14, respectively.

In all, 84 people, including 27 perpetrators, died, and another 136 were injured. Most of the shootings were intentional and perpetrated by males. And more than half occurred in publicly funded schools.

The number of school shootings was lower in states with mandatory background checks for gun and ammunition purchases, higher spending on mental health and K-12 education, and in those with a larger proportion of the population living in towns and cities, the research team found.

The study was led by Bindu Kalesan, assistant professor of medicine at MED, director of the Center for Clinical Translational Epidemiology and Comparative Effectiveness Research, and assistant professor of community health sciences at SPH; and was co-authored by Dean Sandro Galea. Other co-authors were from Columbia University Law School and the Department of Epidemiology, and the University of Texas Southwestern School of Medicine.

Because this is an observational study, no firm conclusions can be drawn about cause and effect, the authors said. Further, media reports are not always the most reliable sources of consistent and comprehensive information, they pointed out. The researchers also did not have information on the perpetrators’ mental health.

Still, they said the rising incidence of school shootings emphasizes the need for a national registry to monitor mass and school shootings, in order to better inform the debate around the drivers and consequences of these traumatic events.