I was expelled from the Socialist Workers Party (SWP, then called IS) on 4 December 1971. IS then was different from, and more open than, the SWP today. But there are links between then and now.
IS (SWP) had deliberately promoted itself as democratic and open since 1957-8, as a riposte to the bigger and more active, but tightly-controlled, SLL led by Gerry Healy (only tiny shreds from which continue today: it collapsed in 1985).
IS really was more open. There was debate in its press. In December 1968, it accepted a merger with the small Trotskyist group Workers’ Fight, forerunner of the AWL,