Active shooter or active killer describes the perpetrator of a type of mass murder marked by rapidity, scale, randomness, and often suicide. The United States Department of Homeland Security defines an active shooter as "an individual actively engaged in killing or attempting to kill people in a confined and populated area; in most cases, active shooters use firearms and there is no pattern or method to this selection of victims."
In police training manuals, the police response to an active shooter scenario is different from hostage rescue and barricaded suspect situations. Police officers responding to an armed barricaded suspect often deploy with the intention of containing the suspect within a perimeter, gaining information about the situation, attempting negotiation with the suspect, and waiting for specialist teams like SWAT.
The terminology "active shooter" is critiqued by some academics. Ron Borsch recommends the term rapid mass murder. Due to a worldwide increase in firearm and non-firearm based mass casualty attacks, including attacks with vehicles, explosives, incendiary devices, stabbings, slashing, and acid attacks, Tau Braun and the Violence Prevention Agency (VPA) has encouraged the use of the more accurate descriptor mass casualty attacker (MCA).
Most incidents occur at locations in which the killers find little impediment in pressing their attack. Locations are generally described as soft targets, that is, they carry limited security measures to protect members of the public. In most instances, shooters die by suicide, are shot by police, or surrender when confrontation with responding law enforcement becomes unavoidable, and active shooter events are often over in 10 to 15 minutes.
According to Ron Borsch, active shooters are not inclined to negotiate, preferring to kill as many people as possible, often to gain notoriety. Active shooters generally do not lie in wait to battle responding law enforcement officers. Few law enforcement officers have been injured responding to active shooter incidents; fewer still have been killed. As noted, more often than not, when the prospect of confrontation with responding law enforcement becomes unavoidable, the active shooter commits suicide. And when civilians—even unarmed civilians—resist, the active shooter crumbles.
Borsch's statistical analysis recommends a tactic: aggressive action. For law enforcement, the tactical imperative is to respond and engage the killer without delay—the affected orthodoxy of cumbersome team formations fails to answer the rapid temporal dynamics of active shooter events and fails to grasp the nature of the threat involved. For civilians, when necessity or obligation calls, the tactical mandate is to attack the attacker—a strategy that has proved successful across a range of incidents from Norina Bentzel (William Michael Stankewicz) in Pennsylvania and Bill Badger in Arizona (2011 Tucson shooting) to David Benke in Colorado.
In the United States, the Federal Bureau of Investigation (FBI) compiles data on active shooter incidents. From 2000 through 2021, the FBI identified more than 430 active shooter incidents, defined as "one or more individuals actively engaged in killing or attempting to kill people in a populated area." In contrast with mass shooting data collection, the FBI active shooter data collection initiative includes incidents with fewer casualties, and excludes domestic and gang-related incidents. In more than 25% of these incidents, the active shooter incident ended when the attacker committing suicide; in 25%, when the attacker fled. Most active shooter incidents are over before law enforcement arrives. When bystanders do intervene, it is more often through physically subduing the attacker rather than returning fire. Active shooter incidents are rarely ended by an armed bystander returning fire. In 22 of these incidents, the active shooter incident ended when the attacker was shot by an armed citizen, off-duty police officer, or security officer. In ten of these incidents, a civilian killed the attacker.
Accounts of why active shooters do what they do vary. Some contend that the motive, at least proximately, is vengeance. Others argue that bullying breeds the problem, and sometimes the active shooter is a victim of bullying, directly or derivatively. Still others such as Grossman and DeGaetano argue that the pervasiveness of violent imagery girding modern culture hosts the phenomenon.
Some argue that a particular interpretation of the world, a conscious or subconscious ontology, accounts for the phenomenon. They argue that the active shooter lives in a world of victims and victimizers, that all are one or the other. The ontology accommodates no nuance, no room between the categories for benevolence, friendship, decency, nor indeed, for a mixture of good and bad. His interpretation of the world may grow out of or be fed by bullying or violent imagery (hence the common obsession with violent movies, books or video games), but it is the absolutist interpretation of his world that drives him both to kill and to die. In The Psychology of the Active Killer, Daniel Modell writes that "The world conceived by the active killer is a dark dialectic of victim and victimizer. His impoverished ontology brooks no nuance, admits no resolution. The two categories, isolated and absolute, exhaust and explain his world. And the peculiar logic driving the dialectic yields a fatal inference: in a world of victims and victimizers, success means victimization."
- Ballistic shield
- Immediate action rapid deployment
- List of massacres
- Running amok
- School shooting
- Spree killer
- Active shooter training
- Buchanan, Larry; Leatherby, Lauren (June 22, 2022). "Who Stops a 'Bad Guy With a Gun'?". The New York Times. Archived from the original on June 22, 2022.
Data source: Advanced Law Enforcement Rapid Response Training Center
- "Active Shooter: How to Respond" (PDF). U.S. Department of Homeland Security.
- "Abstracts Database - National Criminal Justice Reference Service". www.ncjrs.gov.
- Communications, Government of Canada, RCMP, Public Affairs and Communication Services Directorate, Corporate. "Immediate Action Rapid Deployment (IARD) Program". www.rcmp-grc.gc.ca.
- "2016 Preparedness Summit". eventscribe.com. Retrieved 2017-10-04.[dead link]
- Ron, Borsch. "Solo Officer Entry for Active Shooters: Ron Borsch Q&A Part 1". Spartan Cops. Archived from the original on April 3, 2015. Retrieved September 9, 2016.
- Ayoob, Massad (2017). "Chapter 9, Lone Citizen Heroes, Ron Borsch". Straight Talk on Armed Defense: What the Experts Want You to Know. Gun Digest Media. ISBN 978-1-4402-4754-5.
- Czopek, Madison (July 21, 2022). "There's no evidence that shooter at Indiana mall was a CIA asset". Poynter Institute. PolitiFact.
- White, Ed (July 18, 2022). "Rare in US for an active shooter to be stopped by bystander". Associated Press.
- Bikales, James; Villegas, Paulina; Somasundaram, Praveena; Thebault, Reis (July 18, 2022). "Rampage in Indiana a rare instance of armed civilian ending mass shooting". The Washington Post.
- McGee, J.P.; DeBernardo, C.R. "The Classroom Avenger" (PDF). Archived from the original (PDF) on October 30, 2007.
- Vossekuil, B.; Fein, R.; Reddy, M.; Borum, R.; Modzeleski, W. (2002). "The Final Report and Findings of the Safe School Initiative". US Secret Service and US Department of Education.
- Grossman, D.; DeGaetano, G. (1999). Stop Teaching our Kids to Kill. New York: Crown Publishers.
- Modell, Daniel (December 2013). "The Psychology of the Active Killer". Law Enforcement Executive Forum. 13 (4). Retrieved 2021-03-11 – via Ares Tactics.