Casepin
Back to cases

Solved case

Killing of Claire Davis at Arapahoe High School

On December 13, 2013, an 18-year-old student entered Arapahoe High School in Centennial, Colorado, armed with a shotgun, a machete, and Molotov cocktails, and shot 17-year-old student Claire Davis, who died eight days later; the gunman died by suicide the same day.

SOLVED2013

Arapahoe High School, Centennial, Colorado

3 SOURCESUPDATED JUL 2026
Illustrative

On December 13, 2013, a shooting occurred at Arapahoe High School, a public high school in Centennial, Colorado, in the Denver suburbs. According to the school's Wikipedia article, the gunman was an 18-year-old student identified as Karl Pierson. He entered the school armed with a 12-gauge Stevens Model 320 pump-action shotgun, a machete, three Molotov cocktails, and 125 rounds of ammunition.

Pierson reportedly requested to see the school librarian, who also served as the coach of the school's debate team. His demotion from the debate team was described as a contributing motive for the attack.

During the incident, 17-year-old student Claire Davis was shot in the head. She died eight days later as a result of her injuries. Pierson attempted to start a fire using one of the incendiary devices he had brought into the school. After being confronted by a sheriff's deputy working as a school resource officer, Pierson shot himself in the head and died.

Arapahoe High School is described as the flagship school of the Littleton Public Schools District, the largest of the district's three high schools, with an enrollment of 1,820 students. The school has been designated a Blue Ribbon School by the U.S. Department of Education and maintains a long-standing cultural relationship with the Arapaho Nation of the Wind River Indian Reservation in Wyoming, dating to 1993.

Key facts

Victims
Claire Davis
Date
2013
Location
Arapahoe High School, Centennial, Colorado
Case status
solved

Case timeline

  1. 2013-12-13

    An 18-year-old student, identified as Karl Pierson, entered Arapahoe High School armed with a shotgun, a machete, Molotov cocktails, and ammunition; he shot student Claire Davis and later shot himself after being confronted by a school resource officer.

  2. 2013-12-21

    Claire Davis died from her injuries, eight days after being shot.

Best coverage

No coverage has been attached to this file yet.

Know good coverage? Submit it

People

  • Claire Davis

    VICTIM

    17-year-old Arapahoe High School student shot in the head during the December 13, 2013 attack; died eight days later.

  • Karl Pierson

    CHARGED

    18-year-old student identified as the gunman in the December 13, 2013 shooting; died by suicide at the scene after being confronted by a school resource officer, so no prosecution occurred.

Roles reflect public records and court outcomes at the time of writing — supporting citations are on file under Sources.

Places

Arapahoe High School, Centennial, Colorado

39.5819, -104.9610

View on the map

Common questions

What happened to the victim?
On December 13, 2013, an 18-year-old student entered Arapahoe High School in Centennial, Colorado, armed with a shotgun, a machete, and Molotov cocktails, and shot 17-year-old student Claire Davis, who died eight days later; the gunman died by suicide the same day.
Where did the killing happen?
Arapahoe High School, Centennial, Colorado.
What is the current status of the case?
Status: solved.
More cases in Colorado

Sources

  1. ENCYCLOPEDICArapahoe High School (Colorado)Wikipedia · 2026-07-10
  2. PRESSContemporaneous coverage — CNNCNN · 2026-07-10
  3. OFFICIAL / AGENCYContemporaneous coverage — nces.ed.govnces.ed.gov · 2026-07-10

When a file you follow changes — a new development, a correction, fresh coverage — the Dispatch is how you hear about it.

The Casepin Dispatch

A calm weekly briefing from the archive — one case worth understanding, meaningful updates to files you follow, and the best new coverage. You’ll also get the one-time note when the apps land. No gore, no rumor, no drip.