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The Nature, Trends, Correlates, and Prevention of Mass Public Shootings in America, 1976-2018

NCJ Number
Date Published
December 2021
48 pages

This is the Final Research Report of a project that created a database of mass public shooting incidents, offenders, and victims in the United States from 1976 through 2018 and longer as the work progressed.



The study defined a mass public shooting as “any event in which four or more persons, not including the assailant(s), were killed by gunfire in a public setting within a 24-hour period, absent any associated criminal activity (such as robbery, gang conflict, or illicit drug trade).” From these and other data, the following analyses were conducted: 1) An in-depth description of mass public shooting incidents, offenders, and victims compared with general homicide patterns; 2) An evaluation of whether state-level gun legislation, such as concealed carry laws and prohibitions on large-capacity magazines, affect the incidence and severity of mass public shootings; 3) An examination of the incident, offender, and victim characteristics that impact the newsworthiness of mass public shootings; 4) An assessment of the extent to which timing of mass public shootings suggests a contagion effect based on media coverage; 5) A comparison between completed mass shootings and thwarted plots; 6) A forecast of the severity of mass public shootings over the next few decades; and 6) An estimate of the global prevalence of mass public shootings that account for missing data. Data collection for this research has been completed for the period from 1999 to 2019. Researchers are just finishing cleaning the data file and creating numeric codes for all fields where appropriate. 8 figures



Date Published: December 1, 2021