Report says Colorado school missed opportunities to prevent fatal student attack in 2013

Significant procedural and communications failures prevented a Colorado high school from identifying and intervening with a troubled student who unleashed a fatal gun attack in 2013 that killed a fellow student.

The conclusions were contained in a 141-page report completed by Center for the Study and Prevention of Violence at the University of Colorado Boulder, which was asked to investigate the causes of the Dec. 13, 2013, siege at Arapahoe High School in Centennial, Colo.

Karl Pierson, 18, armed with a pump-action shotgun, ammunition, a machete and three Molotov cocktails, entered the school that day through a propped-open door. He shot fellow student Claire Davis, 17, who subsequently died from her injuries. Pierson eventually killed himself in the school library. His intended target was a debate coach who had removed Pierson from a leadership position on the team.

The report identified three major failures within Arapahoe High and the Littleton School District: a failure of information sharing, a failure of threat assessment, and a failure of systems thinking.

“Not one [Arapahoe] teacher, administrator or staff person had a complete record of [Pierson’s] history of concerning behaviors over his more than three years at [Arapahoe], making it challenging to adequately assess the threat he presented," the report says.

The school and the district did not consistently maintain information about Pierson, referred to in the report as KP.

“At least l0 students "had substantive concerns about KP's anger problems and gun ownership....but only one student reported (this) to a counselor...and no students used the school's anonymous reporting system to report concerns,” the report says.

Arapahoe High School also failed to adequately carry out the Littleton School District's threat-assessment policies, and the Littleton district failed to validate the effectiveness of its threat-assessment tool.

"Out of 24 possible risk factors on KP’s threat assessment, only five were checked, and this investigation revealed that seven to nine additional risk factors could have been checked," the report states. "If the threat assessment and follow-up plan had been properly executed, KP’s violent plans might have been interrupted."

The report spells out 32 recommendations for identifying and supporting students in crisis and developing protocols for responding to such students.

"To reach these goals and to help prevent future tragedies, schools and districts must first build safe school climates," the report says. "...The institutional barriers within schools, districts and our culture will need to be dismantled, including the belief that schools are powerless to manage mental health issues."