Lt. Col. Dave Grossman

Lt. Col. Dave Grossman is a retired United States Army officer and a recognized authority in the psychology of lethal force and human aggression. Grossman served as an Airborne Ranger infantry officer with more than 23 years of military experience, including assignments as a West Point psychology professor and Professor of Military Science. He founded the field of killology, a scientific discipline examining the physiological and psychological effects of killing in war and society, the root causes of violent crime, and pathways to healing for survivors of violence.

Grossman is known for his work, "On Killing: The Psychological Cost of Learning to Kill in War and Society," which has sold more than half a million copies worldwide and has been translated into several languages. The book was nominated for a Pulitzer Prize and is required reading at the FBI Academy, the U.S. Marine Corps Commandant's Required Reading List, and numerous military and law enforcement academies globally. He has co-authored a New York Times bestselling book with Glenn Beck and published additional works, including "On Combat" as well as fiction and children's books. His research has been cited by U.S. presidents in national addresses, and he has testified before the U.S. Senate, Congress, and various state legislatures.

After retiring from active duty, Grossman established the Killology Research Group and serves as director of Grossman On Truth, LLC. He conducts seminars and training for military and law enforcement organizations worldwide, delivering presentations to law enforcement professionals, educators, and military personnel across all 50 states and in numerous foreign nations. Grossman has served as an expert witness in state and federal court cases, including the prosecution of Timothy McVeigh, and has provided consultation and training following major violent incidents, including school massacres.

Grossman's work in combat psychology and violence prevention has earned him recognition as a Life Diplomate by the American Board for Certification in Homeland Security and a Life Member of the American College of Forensic Examiners Institute. He has presented papers before major professional organizations, including the American Medical Association, American Psychiatric Association, American Psychological Association, and American Academy of Pediatrics, and has lectured at more than 100 colleges and universities worldwide. His research continues to influence how military personnel, law enforcement officers, and civilians understand the psychological dimensions of lethal force and violence prevention.