In 2013, Aaron Alexis, veteran, Naval reservist, and government contractor, shot and killed 12 people at Naval Sea Systems Command headquarters in Washington, D.C., before being killed at the scene by police. Alexis, like many other active shooters, displayed behavior that if addressed earlier, might have prevented an insider threat attack. The Washington Navy Yard Shooting was the impetus for the establishment of Insider Threat Programs within the Department of Defense.