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New document reveals details about Arapahoe H.S. shooter’s threat assessment

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Emergency response following Arapahoe High School shooting

Emergency response following Arapahoe High School shooting

DENVER — FOX31 Denver obtained new documents related to last December’s deadly shooting at Arapahoe High School in Littleton.

It’s our first look at the threat assessment document which the school created after shooter Karl Pierson threatened to kill his teacher.

In the document administrators said Pierson had the ability to carry out a plan to kill his teacher, but it said he had no access to weapons.

The report also noted Pierson had difficulty controlling his anger and said the staff was fearful of Pierson.

The document was never updated when a school security guard found Pierson researching guns online.

Pierson was also never suspended for the treat.

He entered the school December 13, 2013 and killed classmate Claire Davis before committing suicide inside the building.

Administrators have faced questions about what they knew prior to the attack.