Per Article 160 of the Constitution of Malaysia one must be Muslim to be considered Malay. In practice, Muslims cannot convert to another religion due to the Shari'a courts denying conversion claims, and if a Malay did convert they would lose their status as bumiputera. People of non-Muslim origins are required to convert to Islam if they marry a Muslim person. Public schools are required to offer Islamic religious instruction, although alternative ethics classes are provided for non-Muslims. Many women wear the tudong, which covers the head but leaves the face exposed, although there is no law requiring this. Islamic police monitor the Muslim population. Regulation of sexual activities among the Muslim population is strict, with laws prohibiting unmarried couples from occupying a secluded area or a confined space, to prevent suspicion of acts considered islamically immoral.