The list arose from a conversation held in late 1949 between J. Edgar Hoover, Director of the FBI, and William Kinsey Hutchinson, International News Service (the predecessor of the United Press International) editor-in-chief, who were discussing ways to promote capture of the FBI's "toughest guys".
Listen blev oprettet efter en samtale afholdt i slutningen af ​​1949 mellem J. Edgar Hoover, direktør for FBI, og William Kinsey Hutchinson, chefredaktør for International News Service (forgængeren for United Press International), hvor de diskuterede metoder til at fremme arresstationen af af ​​FBIs "hårdeste fyre".