Mapping Gun Violence: A Detailed Account of U.S. Mass Shootings
CU Firearm Injury Prevention Initiative researcher provides new visual analysis on recent mass shootings that reveals deeper connections to policy, environmental, and socio-cultural factors.
The United States has more than 10 times the number of mass shooting incidents than other developed countries, yet little research has shown the distribution and types of shootings, geographically.
“I’m constantly asked, ‘What is public health doing about the rise in mass shootings?” shares Leslie Barnard, MPH, a student working with the University of Colorado School of Medicine’s Firearm Injury Prevention Initiative.
Barnard, a doctoral candidate in the Department of Epidemiology in the Colorado School of Public Health at the CU Anschutz Medical Campus, wanted to find answers to address public concerns about the shootings from a public health perspective. Barnard worked with CU Firearm Injury Prevention Initiative collaborators to analyze data from 2014–22 and calculate cumulative incidence rates of mass shooting event types based on incident characteristics.
Barnard’s study, published today in the Journal of the American Medical Association (JAMA) Network Open, aims to clarify the ‘why, where, and how often’ of mass shootings to foster a deeper understanding of this public health crisis. Although not designed to answer every question, the study highlights key factors to provoke further research hypotheses.
“We want to help explain the ‘why, where, and how often’ to give people an understanding of this issue,” she says. “This study is not intended to answer every question, but highlights components to generate more hypotheses.”
Understanding Mass Shootings Epidemiology
Barnard and her CU colleagues scrutinized state rates of different types of mass shooting events and the total count of injuries and fatalities in the U.S., leveraging the Gun Violence Archive’s data. This archive identifies a mass shooting as an incident where four or more people are shot or killed, excluding the perpetrator.
The team analyzed data from a nine-year period starting from January 1, 2014, through to December 31, 2022. They calculated the cumulative incidence rates of different types of mass shootings based on incident characteristics and the total number of injured and killed per 1 million people.
From 2014–22, the United States experienced 4,011 mass shootings, ranging from none in Hawaii and North Dakota to 414 in Illinois, with Colorado reporting 60 incidents. Over this period, 27% were social-related mass shootings, 16% crime-related, 11% domestic violence-related, 1% school- or work-related, and the remaining 52% did not fit into these categories, cumulating in a staggering 21,006 casualties.
“From this data, we can speculate that certain communities and victims are underrepresented,” Barnard adds. “Mass shootings in public places are covered by media, but 11% of mass shootings are domestic violence-related and even more may never be reported or receive coverage. We ask ourselves how we can raise awareness and bring support to this issue.”
Looking ahead, Barnard believes future research should evaluate socioeconomic, political, cultural, and demographic factors linked with mass shooting incidents across states and address state policies and health determinants associated with mass shooting incidents.
When comparing Colorado’s mass shooting statistics with other states, Emmy Betz, MD, MPH, director of the Firearm Injury Prevention Initiative and professor of emergency medicine, explains, “Our state is about average. We rank 22nd in the number of mass shootings and population-based rate of mass shootings.”
“I’m often asked how Colorado compares to other states. This work shows that our state is in the middle. We have the 22nd highest number of mass shootings and population-based rate of mass shootings,” points out Emmy Betz, MD, MPH, director of the Firearm Injury Prevention Initiative and professor of emergency medicine at the CU School of Medicine.
Preventing Mass Shootings in the US
Although Barnard’s visual analysis strives to help the public grasp the context of mass shootings, she acknowledges existing discrepancies that obstruct understanding and prompt action. She notes that the definition of ‘mass shooting’ varies from one source to another, which poses challenges, especially for epidemiologists requiring a unified definition for accurate reporting.
Barnard is hopeful that public access to visual data, such as that provided by her study, will help solidify the definition of “mass shooting” by illustrating the number of victims and can be utilized for state-level prevention strategies.
Ashley Brooks-Russell, PhD, MPH, co-author and director of the Injury and Violence Prevention Center, supports this view.
“Understanding where mass shootings occur across the country, and more about the context, such as how often these tragic events happen in homes, can point firearm injury prevention specialists toward how to prevent them,” the co-author adds.
Barnard emphasizes the crucial role of the Firearm Injury Prevention Initiative in catalyzing change and sparking her passion to draw more attention to firearm injuries.
“The ways I’ve been supported by Emmy and the initiative’s leadership team are invaluable to this research and future studies,” she concludes.
Image Credit: Theodore Parisienne for NY Daily News via Getty Images