Spatial Patterns of Mass Shootings in the United States, 2013–2014

There were 374 mass shootings in the United States between 2013 and 2014 and they were not random occurrences. We expanded the FBI’s definition of mass shootings (four or more injured or killed, not including the shooter), and collected data on every mass shooting that occurred in the United States to observe geographical patterns. Social Disorganization theories state that violence will occur in areas with high levels of poverty, large population density, and little economic opportunity. These theories work well with strain theory, which suggests that blocked goals, the introduction of a negative stimulus, or the removal of a positive stimulus leads to negative emotions, and these emotions can lead to crime in order to resolve the strain felt. From under this framework, we discover with point pattern analysis that there are patterns in the location of mass shootings crime scenes. They are not random. These crimes were far more likely to occur in the South, the Upper Midwest, and in Southern California, while they were considerably less likely to occur in the Pacific Northwest, Upper Midwest, or the Northeast. The lack of random spatial pattern indicates that the structural factors that contribute to mass shootings are more prevalent in certain areas of the United States than in others.