By Brent R. Klein,  Cory Schnell,  Steven M. Chermak,  Joshua D. Freilich

This study examined firearm lethality and lethal intent on injurious fatal and nonfatal school shootings using data from The American School Shooting Study, which covers 329 school shootings in the United States from 1990 to 2016. We developed a new multidimensional construct for measuring determination to kill and examined firearm characteristics while considering confounding factors. We identified 11 distinct categories of shooters’ intent, with most showing a strong desire to kill. Both intent and weapon lethality significantly impacted school shooting homicides. Overall, we recommend that prevention and theoretical models should address both factors.

Criminology. 2025;63:673–686.