The Valachi hearings, also known as the McClellan hearings, investigated organized crime activities across the United States. The hearings were initiated by Arkansas Senator John L. McClellan in 1963. Named after the major government witness against the American Mafia, foot soldier and made man Joseph Valachi, the trial exposed American organized crime to the world through Valachi's televised testimony.[1] At the trial, Valachi was the first member of the Italian-American Mafia to acknowledge its existence publicly, and is credited with popularization of the term cosa nostra.[2] The trial also exposed the hierarchy of the American Mafia, including the Five Families and The Commission.