By religious legal pluralism we usually mean state-recognised legal pluralism, such as the kind of legal pluralism implemented in Singapore through the Administration of Muslim Law Act. But there is also religious legal pluralism outside State recognition and enforcement. Many religions have very long legal traditions which have survived, often without much support or official recognition by States (Jewish law, for example). In this paper we shall look at one such tradition, the canon law of the Latin Church of the Roman Catholic Church and its implementation by the Church in Singapore, including the establishment of very busy ecclesiastical tribunals in Singapore to administer disputes relating to the possible nullity of religious marriages, for example. The hope is that this example of Canon Law in Singapore will show that there can be very detailed and formal religious laws implemented by formal institutions such as tribunals outside the ambit of the State.