Under the Duplessis regime, some of the founders of the League were already very active in the defense of human rights in Canada.
This is particularly the case of Frank Scott, who founded the Canadian Society for Human Rights in 1937, Thérèse Casgrain, pioneer in the fight for women's suffrage and founder of the League for Women's Rights, Pierre Elliot Trudeau, who participated in the creation of several groups intended to federate the opposition forces to the duplessist regime in the second half of the 1950s.
Léon Patenaude, Jacques Hébert, and Gérard Pelletier joined them to launch the Ligue des droits de l'homme on May 29, 1963, in Montreal.
[1] The organization is committed to upholding the principles of the Universal Declaration of Human Rights.
Jacques Hébert served as president of the union for part of this period and opposed Trudeau's use of the War Measures Act to resolve the FLQ Crisis.