Active shooter definition

Active shooter incidents are a subset of gun violence characterized by an individual or individuals actively shooting or attempting to shoot people in a populated area.

Gun violence broadly encompasses all forms of harm involving firearms, such as homicides, gang and drug violence, accidental shootings, and domestic violence.

However, active shooter events are distinct due to their dynamic, public, and unpredictable nature. Understanding this difference is crucial for targeted prevention strategies to reduce active shooter incidents.

Active shooter incidents are a subset of gun violence. It is important to note that not all violent firearm crimes are considered active shooter attacks; many are excluded from FBI active shooter reports for specific reasons detailed in the methodology section.

The FBI defines an active shooter as one or more individuals actively engaged in killing or attempting to kill people in a populated area.

Characterized by their ongoing nature, these situations offer a crucial window during which both citizens and law enforcement have the potential to intervene and save lives.

An active shooter incident must involve a shooter or shooters using a firearm—whether they successfully discharge the weapon or merely attempt to do so while attempting to kill or harm people.

Notably, some active shooter incidents may not result in casualties due to firearm malfunctions, missing intended targets, or interventions by citizens, security personnel, or law enforcement.

Conversely, not all firearm related incidents qualify as active shooter incidents, such as: • | Gang violence • | Drug-related violence • | Residential or domestic disputes • | Self-defense • | Barricade/Hostage situation • | Shootings in relation to another criminal act • | Crossfire as a byproduct of another ongoing criminal act

The FBI defines Active Shooter as, “one or more individuals actively engaged in killing or attempting to kill people in a populated area.”

This report focuses on a particular type of firearm violence, and the data it provides might differ from those used in broader categories like mass shootings or mass killings.

The terms “mass shooting” and “mass killing” are sometimes used interchangeably, and they can overlap with what are called active shooter incidents.

While some attacks can fall into more than one of these categories, not every mass shooting or mass killing meets the criteria of an active shooter incident.

To help make these distinctions clear, the following chart differentiates the characteristics of active shooter attacks, mass shootings, and mass killings.

Note: All injuries and fatalities do not include the shooter.

Definition | One or more individuals actively engaged in killing or attempting to kill people in a populated area | Three or more individuals injured and/or killed in a single incident | Three or more individuals killed in a single incident excluding the shooter

Requires Use or Attempted Use of | Yes | Yes | No Firearm

Number of Casualties Required | None | At least three | At least three fatalities

Exclusionary Factors • | Gang violence • | Drug-related violence • | Residential or domestic disputes • | Self-defense • | Barricade/Hostage situation • | Shootings in relation to another criminal act • | Crossfire as a byproduct of another ongoing criminal act None None

46 Refers to the FBI’s definition of an active shooter.

ACTIVE SHOOTER (FBI DEFINITION): one or more individuals actively engaged in killing or attempting to kill people in a populated area