• 3 Columbine High School Massacre, Littleton, Colo., 1999
• 3 Law and legislation
• 3 Marijuana
• 3 School violence
• 2 Drug legalization
• 1 Citizen suits (Civil procedure)
• 1 Filicide
• 1 Holmes, James, 1987-
• 1 Marijuana industry
• 1 Mass murder investigation
• 1 Mass murderers
• 1 Moral and ethical aspects
• 1 Prisoners
• 1 Prisons
• 1 Sex change
• 1 United States Penitentiary, Florence, Colorado

• 3 Bradley, Ed, 1941-2006
• 3 Gelber, David
• 3 Malmgren, Helen
• 2 Pelley, Scott, 1957-
• 1 Anderson, Robert
• 1 Arledge, Elizabeth
• 1 Devine, L. Franklin
• 1 Doane, Seth, 1978-
• 1 Laudato, Anthony
• 1 Lieberman, Marc
• 1 Petersen, Barry (Barry Rex), 1949-
• 1 Schuster, Henry
• 1 Wallace, Mike, 1918-2012
• 1 Whitaker, Bill

• 10 English

• 3 Littleton
• 1 Aurora
• 1 Castle Rock
• 1 Florence
• 1 Trinidad
• 1 United States

• 10 Television news programs
• 1 Biographical television programs
• 1 Biography

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