page_title: Mass shooting
section_title: United States
hierarchical_section_title: Mass shooting / By continent and region / North America / United States
caption_attribution_description: English: Total deaths by year of all spree shootings; data from http://www.motherjones.com/politics/2012/12/mass-shootings-mother-jones-full-data Español: Muertes totales por año de all spree shootings. Français&#160;: Nombre de tués par an par fusillades aux Etats-Unis
context_page_description: A mass shooting is an incident involving multiple victims of gun violence. There is no widely accepted definition of the term mass shooting. The United States' FBI follows the Investigative Assistance for Violent Crimes Act of 2012 definition for active shooter incidents and mass killings in public places. Based on this, it is generally agreed that a mass shooting is whenever three or more people are shot, not including the shooters.
  Different media outlets and research groups use different definitions for the term "mass shooting" For example, crime violence research group Gun Violence Archive defines a "mass shooting" as "four or more shot in a single incident, at the same general time and location, not including the shooter, ” differentiating between mass shooting and mass murder and not counting shooters as victims.
  The United States’ Congressional Research Service acknowledges that there is not a broadly accepted definition and defines a "public mass shooting" as an event where someone selects four or more people and shoots them with firearms in an indiscriminate manner, echoing the FBI's definition of the term "mass murder", but adding the indiscriminate factor.
context_section_description: The United States has had the most mass shootings of any country.
  In one 2017 study published in Time magazine by criminologist Adam Lankford, it was estimated that 31% of public mass shootings occur in the US, although it has only 5% of the world's population. The study concludes that “The United States and other nations with high firearm ownership rates may be particularly susceptible to future public mass shootings, even if they are relatively peaceful or mentally healthy according to other national indicators.”
  Criminologist Gary Kleck criticized Lankford's findings, stating the study merely shows a proportional relationship, but fails to prove that gun ownership causes mass shootings. Kleck claims that Lankford has been unwilling to share a list of his cases, provide a list of the number of attacks per country, or even list his sources so that others can check his numbers.  Backlash from economist and gun rights advocate John Lott also raised objections to Lankford's methodology and refusal to share his data. He speculated that Lankford had overlooked a significant number of mass shootings outside the US, which if accounted for would adjust the nation's share closer to 2.88%; slightly below the world average.  Adam Lankford has since followed up on his research, clarifying that although the United States is not significantly more likely than most other countries to have mass shootings that are committed by more than one person, such as the university massacre in Kenya, the United States from 1998-2012 did in fact have more than six times its global share of public mass shooters who attacked alone. Using the data from Lott and Moody's 2019 study of mass shootings, Lankford explains that "41 of all 138 public mass shootings by single perpetrators worldwide were committed in the United States. That represents 29.7%. Because America had in those years approximately 4.5% of the world's population (according to Lott and Moody's calculations), this indicates that based on their own data, the United States had more than six times its global share of public mass shooters who attacked alone (29.7/4.5 = 6.6).  
  Mass shootings have also been observed to be followed by an increase in the purchase of weapons, but does not seem to create an increased feeling of needing guns in either gun owners or non-owners.
caption: Total U.S. deaths by year in spree shootings: 1982 to current (ongoing).[24]
exif: {}