Prior to Maithripala Sirisena, S.B. Dissanayake, who was the General Secretary of the party, during former President Chandrika Bandaramaike Kumaratunga’s time, also left the party and joined the UNP. Maithripala was elevated to the position of General Secretary after S.B. Dissanayake’s crossover.
Former Prime Minister Rathnasiri Wickramanayake too distanced himself from the party in the mid 80 and stepped down from the party due to internecine battles in the SLFP which was then in the opposition.
J.R.P. Sooriyapperuma, who is now a national list Parliamentarian of the United People’s Freedom Alliance (UPFA), was the General Secretary of the party. He crossed over to the SLFP from the UNP and later distanced himself from active politics due to internal crises in the SLFP in early 90s.
Rathna Deshapriya Senanayake, who started his political career from the Communist Party, is another General Secretary of the SLFP who left the party. His brother, Dharmasiri Senanayake too, became the General Secretary of the Sri Lanka Freedom Party and he was the only General Secretary of the SLFP to remain in the post without leaving the party. However, it was widely rumored Senanarake too would leave the party due to differences of opinion with CBK.
Bernard Aluvihare, founding General Secretary of the SLFP, also crossed over to the UNP in 1956, just months before the general election. However, Aluvihare, ended up in the losing party and failed to secure his seat in Parliament. He lost to Nimal Karunathilake, a journalist attached to the lankadeepa newspaper, who was fielded by Bandaranaike at the last moment.
Nimal karunathilake too crossed over to the UNP along with C.P. de Silva in 1964. CP’s crossover, which was engineered by Esmond Wickremesinghe in 1964, resulted in the downfall of the SLFP led government, headed by the late Sirimavo Bandaranaike. Esmond Wickremesinghe is the father of Ranil Wickremesinghe who is the present National Leader of the United National Party.