top of page

What is an Active Shooter?

Updated: Feb 12, 2022


Active shooter incidents in the United States (US) have increased an average of 27% a year for twenty years (2000-2019).[i] These tragedies occur in nearly every corner of civil society, impacting schools, businesses, religious institutions and first responders. In this article, we will define what an active shooter is, explain key findings from Federal Bureau of Investigation (FBI) data, and provide steps you can take to prepare against this threat. [ii]

What is an Active Shooter?

An “active shooter” is defined by the US government as “an individual actively engaged in killing or attempting to kill people in a confined and populated area”. The use of a firearm is implied, but not explicitly stated. "The FBI expands this definition to include more than one individual in an incident and omits the word confined as the term excludes incidents that occurred outside buildings." The term, as defined by the FBI, excludes firearm incidents resulting from events such as drug or gang related violence, self-defense, contained residential or domestic disputes, controlled barricade or hostage situations, cross-fire as the result of another criminal act, or an action that did not seem to put other people in peril.

How frequent are Active Shooter incidents?

US Active shooter events: 2000-2019. Active shooter definition. What is an active shooter? Active shooter statistics.

Active shooter events in the United States increased an average of 27% a year for twenty years from 2000 to 2019 according to an analysis of Federal Bureau of Investigation (FBI) data. Average yearly increase was calculated using the Average Annual Growth Rate method. [iii]

Findings by the FBI for 2020 and 2021 were not available by publication. However, anecdotal indications suggest a sharp decline in active shooter events in 2020 due to COVID-19 related restrictions followed by a return to the previous 20 year trajectory in 2021.

What is a Mass Shooting?

To learn more about mass shooting definition, please see "What is a Mass Shooting?"

What causes these tragedies?

Unfortunately, reputable research is sparse on the causes of active shooter and mass killing behaviors. Funding for research, however, has increased over the past few years. While no cure-alls have been discovered, some studies have begun to provide quantifiable insights on the value of preventative measures such as early warning, new response protocols, and building design.

What do we know about Active Shooter events from the FBI?

  • Most active shooter events last five minutes or less. This means potential victims and law enforcement must react quickly. In incidents from 2000 to 2013 where the duration could be determined, 69% ended within five minutes.

  • Half are over before law enforcement arrives. A review of incident data from 2000 through 2019 show that 51% of Active Shooting events, or 157 out of 305, ended prior to the arrival of law enforcement. This includes occasions where the perpetrator committed suicide, was stopped by or surrendered to civilians, or fled the scene only to be confronted by law enforcement at a different location.

  • Civilian confrontation of the shooter occurs only occasionally. While citizens, armed and unarmed, have acted bravely to end some active shooter incidents, these instances make up a relatively small percentage of outcomes from 2000-2019, comprising only 16% of resolutions, or 48 out of 305.

  • Law enforcement is the primary means of resolution for apprehending an active shooter. In some cases, this occurs after the shooter has fled the scene.

  • Half of law enforcement confrontations end with an officer casualty. Once law enforcement confronts the shooter, the odds that they will be killed or wounded are high with 51% of incidents, or 47 out of 93 from 2000-2019 resulting in a law enforcement casualty. 2000-2013, 2014-2015, 2016-2017, 2018, 2019.

  • Commercial locations experience the most incidents, followed by education facilities. Commerce experienced 44%, or 133 out of 305, of active shooter events, followed by education which experienced 20%, or 60 out of 305, of occurrences from 2000-2019. See the detailed 2000-2018 location breakdown here.

  • Most active shooters are male. Males comprised 96%, or 311 out of 324, of active shooters from 2000-2019. Females comprised 4%, or 13 out of 324, during the same period.

US active shooters by age. Active shooter statistics. Active shooter definition.
  • Shootings appear to be most often committed by individuals 20-29 years old. This data is incomplete, however, as age data is only available for 133 of 305 incidents from 2000-2019.

What can I do to prepare against this threat?

While there is no cure-all, there are still a variety of steps you and your organization can take to reduce the chances and severity of a potential active shooter attack. Specific best-practices will vary by context, but some options to consider are as follows:

Where can I find more resources on this topic?

You can get a free list of resources by requesting it here. We regularly review new material to keep our holdings current. If you know of good resources not listed, please let us know.



[i] Comment: While active shooter incidents have occurred much farther back in US history, a lack of consistent, reputable research makes it difficult to characterize the period prior to 2000. The author welcomes good-faith contributions to put the 2000-2019 trend in a broader historical context.

[ii] Scope note: The active shooter subject understandably evokes strong feelings across the political spectrum. This article does not take a stand on the subject of gun rights or gun control.

[iii] Comment: Annual percentage increase calculation updated to use the Average Annual Growth Rate (AAGR) method.

Recent Posts

See All


Commenting has been turned off.
bottom of page