After its defeat in the 1979 general election the Labour Party underwent a period of internal rivalry between the left represented by Tony Benn, and the right represented by Denis Healey. The election of Michael Foot as leader in 1980, and the leftist policies he espoused, such as unilateral nuclear disarmament, leaving the European Economic Community (EEC) and NATO, closer governmental influence in the banking system, the creation of a national minimum wage and a ban on fox hunting led in 1981 to four former cabinet ministers from the right of the Labour Party (Shirley Williams, William Rodgers, Roy Jenkins and David Owen) forming the Social Democratic Party. Benn was only narrowly defeated by Healey in a bitterly fought deputy leadership election in 1981 after the introduction of an electoral college intended to widen the voting franchise to elect the leader and their deputy. By 1982, the National Executive Committee had concluded that the entryist Militant tendency group were in contravention of the party's constitution. The Militant newspaper's five member editorial board were expelled on 22 February 1983.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What did four members of the Labour Party leave to creat?
Social Democratic Party