Islamic religious police (also sometimes known as morality police or sharia police) are official Islamic vice squad police agencies, often in Islamic countries, which enforce religious observance and public morality on behalf of national or regional authorities based on its interpretation of sharia. Modern Islamic religious police forces were first established in the late-1970s amidst the Iranian Revolution and the Islamic revival the revolution brought; prior, the administration of public morality in most Islamic countries was considered a socioreligious matter, and was enforced through application of civil laws or through more informal means. The powers and responsibilities of Islamic religious police vary by country, but in contrast to the enforcement of laws against crimes like robbery and murder by conventional police forces, Islamic religious police have focused more on such issues as preventing the consumption of alcohol, mixing of men and women, playing of music and public display of affection, western practices such as Valentine's Day or Christmas gifts, making sure women (but also sometimes men) observe Islamic dress code, and that Muslims are not skipping salat prayer attendance. They are sometimes portrayed as parapolice forces that mostly give citations and warnings, but in most countries they have powers similar to sworn police officers, including the power to detain people. The practice is generally justified with reference to the doctrine of hisba, which is based on the Quranic injunction of enjoining good and forbidding evil, and refers to the duty of Muslims to promote moral rectitude and intervene when another Muslim is acting wrongly. In pre-modern Islam, its legal implementation was entrusted to a public official called muhtasib (market inspector), who was charged with preventing fraud, disturbance of public order and infractions against public morality. This last part of public morality was missing in early and medieval Islam but the office was revived in Saudi Arabia, and later instituted as a committee, aided by a volunteer force focused on enforcing religious observance.