Active shooter

Active killer or active shooter names the perpetrator of a type of mass murder marked by rapidity, scale, randomness and suicide.

The United States Department of Homeland Security defines the 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(s) [sic] and there is no pattern or method to their selection of victims." 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 commit suicide, are shot by police, or surrender when confrontation with responding law enforcement becomes unavoidable. According to New York City Police Department (NYPD) statistics, 46 percent of active shooter incidents are ended by the application of force by police or security, 40 percent end in the shooter's suicide, 14 percent of the time the shooter surrenders and, in less than 1 percent of cases, the violence ends with the attacker fleeing, although the report provides no formal definition of the relevant terms and, as a result, the scope of its statistical findings is somewhat ungrounded.

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.

If police officers believe that a gunman intends to kill as many people as possible before committing suicide, they may use a tactic like Immediate Action Rapid Deployment.

The terminology "active shooter" is critiqued by some academics. There have been several mass stabbings that have high casualty counts, for instance in Belgium (Dendermonde nursery attack), Canada (2014 Calgary stabbing), China (2008 Beijing Drum Tower stabbings), Japan (Osaka School Massacre), and Pennsylvania (Franklin Regional High School stabbing). Ron Borsch recommends the phrase "rapid mass murder".

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Wikipedia