 On 25 January 1981, Roy Jenkins, David Owen, Shirley Williams and Bill Rodgers (known collectively as the "Gang of Four") launched the Council for Social Democracy, which became the Social Democratic Party in March.The "Gang of Four" left the Labour Party because of what they perceived to be the influence of the Militant tendency and the Bennite "hard left" within the party.Benn was highly critical of the SDP, saying that "Britain has had SDP governments for the past 25 years."