Laws and regulations enacted by a government. Qanun were meant to be supplements to Islamic law in matters it left insufficiently regulated. Under the Ottoman sultans, qanun became an integral part of the legal system, especially in the administrative, fiscal, and penal domains. The sultan's prerogative to enforce customary practices deemed publicly beneficial was a main justification of qanun. In the modern era, qanun gradually became a generic name for all laws and regulations. Similar developments took place in other Muslim countries under such different names as dustur and nizam.