RPM Special Edition on School Violence:
Summary of Patterns in the Incidents

Last Updated: March 27, 2013

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Special Edition on School Violence

Violence is not a new phenomenon in American schools. We found reports dating to the 1800s in which students killed someone else in school, often a teacher whom the student thought had administered discipline unfairly.

The nation’s most deadly school violence incident occurred in 1927 in Bath, Michigan, when a school board member bombed the Bath Consolidated School, killing 45 people, including 38 children.

The first mass shooting in an American K–12 school occurred in 1974 when a 17-year-old senior entered his high school in Olean, New York, over the Christmas break and fired randomly onto the street below, killing three and injuring 11.

Major patterns

We found accounts of incidents in all kinds of schools: public, private, charter, alternative, religious; and in all locales: rural, small town, urban, and suburban.

Assailants ranged in age from six to 66. Adult assailants included former students, local residents, and persons with no known relation to the school. A substantial number of adult assailants were reported to be over 30 years old. Student assailants came from a variety of family backgrounds, income levels, and ethnicities. They included honors students and popular athletes as well as students with social difficulties or disabilities.

Accounting for the 700 incidents we identified, we found the following major themes:

Most violent school deaths occur in Single events, usually as part of personal altercations, not in Mass Violence incidents like Newtown or Columbine.

  • Three times more people died in Single events than in Mass Violence events, and we note that Single events are under-counted in the report because they were more difficult to research and confirm in media reports.
  • Single events account for about two-thirds of all incidents in the report, with mass violence, threatened mass violence, accidental gun discharges, and hostage events making up the remaining third.

Students, not intruders, are responsible for most incidents in middle and secondary schools.

  • Insiders (students) accounted for nearly three-fourths of all deaths in the incidents we were able to identify.
  • Intruders accounted for a little over 10% of all incidents.
  • Unknown assailants and groups accounted for a little over 10% of all incidents.

Intruders target elementary schools.

  • About a third of all On-Campus Single events in elementary schools were perpetrated by adult intruders. Another quarter of Single event incidents in elementary schools were child suicides.
  • An adult perpetrated all but one Mass Violence events in elementary schools. Several elementary school incidents, including the one non-adult perpetrator, involved shooters firing at students from off-campus positions.
  • 40% of all incidents perpetrated by an adult occurred in elementary schools, although elementary schools accounted for only about 10% of all incidents.

In some communities students are at serious risk while traveling to and from school.

  • Between 10% and 15% of student deaths occurred while students were traveling to or from school and were not on a school bus or at a school bus stop.
  • Unknown assailants accounted for nearly half of these incidents.

The most common weapons of death are guns.

  • Across all events, shootings accounted for a little more than 75% of deaths. Stabbings/slashings accounted for about 15% of all deaths; and, beatings accounted for about 10% of deaths.
  • In Mass Violence school incidents, shootings accounted for 99% of deaths and 76% of injuries.

The majority of incidents occur in high schools.

  • 70% of all incidents occurred in high schools; 20% occurred in middle schools; and 10% occurred in elementary schools.

Types of Incidents.

  • Single event violence accounted for almost two-thirds of incidents.
  • Mass Violence events accounted for a little more than 10% of incidents.
  • Threatened Mass Violence accounted for a little less than 10% of the incidents.
  • Accidental Gun Discharges with no death accounted for a little less than 10% of incidents.
  • About 5% of incidents were Hostage events with no physical injuries.

In-progress events were usually ended by one of the following occurrences:

  • The assailant fled;
  • A teacher, administrator, or classmate tackled or talked down the assailant;
  • Weaponry malfunctioned or the assailant ran out of ammunition;
  • Suicide;
  • The assailant surrendered or was wounded or killed by an armed authority.


Read more from the RPM Special Edition on School Violence.