Gunman, 18, wounds classmate at Arapahoe High School

Arapahoe County Sheriff Grayson Robinson holds a picture of Claire Davis the 17-year-old student that was shot during a briefing Saturday, Dec. 14, 2013, at Arapahoe High School in Centennial, Colo. Davis was shot by 18-year-old shooting suspect Karl Halverson Pierson at the school on Friday before he took his own life. (AP Photo/Ed Andrieski)
Arapahoe County Sheriff Grayson Robinson holds a picture of Claire Davis the 17-year-old student that was shot during a briefing Saturday, Dec. 14, 2013, at Arapahoe High School in Centennial, Colo. Davis was shot by 18-year-old shooting suspect Karl Halverson Pierson at the school on Friday before he took his own life. (AP Photo/Ed Andrieski)