Investigators are looking into what caused 18-year-old Karl Halverson Pierson to open fire at his high school, killing himself and injuring a fellow student
Investigators are looking into what caused 18-year-old Karl Halverson Pierson to open fire at his high school, killing himself and injuring a fellow student. Classmates who knew Pierson say he was outgoing with good friends and had excellent grades. Barry Petersen reports.
