Rudolph Carl Lambert was an American citizen and head of the California Communist Party Labor Commission and also headed of its security section in the 1940s. Lambert first fell under FBI scrutiny in connection with its Comintern Apparatus investigation. Lambert is named in a 1945 San Francisco KGB cable intercepted and deciphered by the Venona project discussing information about uranium deposits in Western states. Lambert figured prominently in the U.S. Atomic Energy Commission's investigation and decision to relieve Dr. J. Robert Oppenheimer, Director of the Manhattan Project at Los Alamos, of his security clearance because of documented close associations which Oppenheimer repeatedly denied, yet ultimately admitted to. In a subsection review 'As to "character"' on 29 June 1954 in the Decision in the Matter of Dr. J. Robert Oppenheimer, the Commission wrote,