Mass Shootings in the United States: An Exploratory Study of the Trends from 1982-2012




Dillon, Luke

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Past studies on mass murder have included public mass shootings along with familicides, felony murders, and gang associated murders. While all of these instances involve the murders of four or more people, there are not many other similarities between each classification. Therefore, public mass shootings are not truly accounted for in previous studies since they are rare events as opposed to familicides. This thesis examined in depth all public mass shootings occurring from 1982 to 2012 in the U.S. Specifically, trends in overall incidents, offense characteristics, and use of weapons were analyzed. The findings indicated that mass shootings are increasing slightly with almost half of all mass shootings analyzed occurring in the past eight years. Meanwhile, the trend of mass shooting incidents was not consistent with general homicide and stranger homicide levels which have decreased over the same time period. When assessing trends in offense characteristics, the significant findings were that offenders are becoming younger, mental illness is becoming an increasing factor, and venues for mass shootings are moving away from the more common workplace shootings of the 1980s. Additionally, assault weapons or large capacity magazines were used in more than half of all cases with significant increases in fatalities, injuries, and total victim counts identified.



Mass shootings, Assault weapons, Trends, Gun control