Sarath Amunugama and Others v. Karu Jayasuriya, Chairman, United National Party and Others – sllr 2000 volume 1 page 172

In the case between Sarath Amunugama and others (Plaintiffs, Members of Parliament expelled from the United National Party) and Karu Jayasuriya, Chairman of the United National Party, and others (Defendants), the court addressed the validity of expulsions effected under Article 99(13)(a) of the Constitution, focusing on whether party disciplinary proceedings adhered to principles of natural justice and procedural fairness. It was held that the summary expulsion of the plaintiffs without adequate notice, a hearing, or a proper disciplinary process constituted a violation of procedural fairness, rendering the expulsions null and void. The judgment reaffirmed the principle that internal party discipline must comply with established rules of natural justice, particularly the audi alteram parte