The Maintenance of Religious Harmony Act was passed in 1990 and gives the minister power to issue a restraining order against a religious leader or member who causes ill will between groups, promotes a political cause under cover of religion, or carries out subversive activity. An order can bar a person from addressing congregations or publishing, and for its first three decades no order was ever issued, which the government treats as evidence that it works and critics treat as evidence that it is unnecessary. Amendments in 2019 added powers to require the removal of online content quickly and to compel religious organisations to disclose foreign donations and foreign affiliations.
The framework does not stand alone. Sedition law was used in 2015 against a teenage blogger for remarks about Christianity, restrictions on public assembly apply to religious gatherings as to any other, and two groups remain deregistered: Jehovah's Witnesses, banned in 1972 because refusal of national service was judged incompatible with conscription, and the Unification Church, deregistered in 1982.
Muslim affairs are administered separately through the Islamic Religious Council under the Administration of Muslim Law Act, which governs mosques, halal certification, the collection of zakat and a Sharia court for family matters. The state's position is that plural societies do not stay peaceful on their own, and that argument is made openly rather than implied.