Active Shooter Events
Introducing Sharing Information to Stop Mass Shootings (SISMS): A short report on a behavioral and event-level dataset for the study of mass public shootings
This short report introduces Sharing Information to Stop Mass Shootings (SISMS), a new behavioral and event-level dataset built to support research on mass public shootings in the United States. The dataset currently documents 171 incidents and 175 perpetrators occurring between 1999 and 2024 for which pre-attack warning behaviors or leakage could be confirmed, drawing on public records, official documents, and triangulated open-source reporting.
Officer Stress & Performance
Box breathing and prolonged exhalation reduces markers of physiological stress reactivity in response to a virtual Trier Social Stress Test
This randomized controlled trial tested whether simple breathing techniques can blunt the body's stress response during an acutely stressful task. Sixty-six participants were assigned to normal breathing, prolonged exhalation, or box breathing before completing a virtual version of the Trier Social Stress Test, a standardized laboratory stress challenge.
Public Opinion & Legitimacy
Striking or grappling? Comparing public and officers' perceptions of police use of force
This experiment showed short video clips of a police encounter to nearly 1,000 civilians and 744 law enforcement officers, with the clips varying in the type of force used, either a punch or a takedown, as well as the races of the officer and the suspect. Both civilians and officers consistently rated the takedown as more professional and appropriate than the punch, with takedown officers receiving excellent ratings roughly 15 to 25 percentage points more often across both groups.
Officer Stress & Performance
Clarifying methods and interpretations in law enforcement mortality surveillance: Response to Kamal
This brief responds to a published commentary raising methodological concerns about a 2025 ALERRT study on law enforcement officer mortality. The authors address questions about how occupation is recorded in mortality data and the potential for statistical bias, explaining the reasoning behind their original analytical decisions.
Public Opinion & Legitimacy
Public opinion and the immediate entry dilemma: A factorial survey experiment on active shooter response
This study measured what the general public thinks law enforcement officers should do when responding to active shooter events, using two national samples in which participants evaluated more than 15,800 fictional scenarios depicting different officer decisions. Law enforcement officers are most influenced by active threat cues like gunfire or injured victims, but citizens based their judgments primarily on the location of the event, strongly supporting immediate police entry in schools and at parades while being more accepting of a delayed response in settings like large shopping malls.