This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Sharia is a single body of religious law, but comparative-law scholarship classifies it as one of the world's great legal families precisely because no two states that apply it give it the same legal weight. In Saudi Arabia, the 1992 Basic Law of Governance names the Quran and Sunna as the constitution itself, so Sharia sits at the top of the legal order, applied by general Sharia courts and, for administrative disputes against the government, by the separate Board of Grievances. In Iran, the relationship is one step removed: an elected parliament passes ordinary legislation, but nothing it passes stands unless the Guardian Council, twelve jurists half named by the Supreme Leader and half nominated by the judiciary, certifies that the law conforms to Islamic criteria. Sharia there is less the whole of positive law than its outer limit.
Move further along the spectrum and the state stops applying Sharia as public law at all. Malaysia and the northern states of Nigeria carve out a defined domain, generally personal status and, in parts of Nigeria, some criminal law, where Sharia courts sit alongside a general secular system that governs everything else. In England and Wales, Sharia has no state-law status whatsoever. Sharia councils and bodies such as the Muslim Arbitration Tribunal, formed in 2007, operate purely as private arbitration under the Arbitration Act 1996, a law that lets two parties agree in advance to have a civil dispute decided under a chosen set of rules, religious or otherwise. Criminal law and divorce sit entirely outside what the Act allows an arbitrator to touch, and a panel award carries legal force in England only because the ordinary civil courts enforce an unchallenged arbitration award of any kind, not because Sharia itself has any standing there.
Four jurisdictions, four different answers to the same question: what happens when this body of law meets the machinery of a state. Comparative-law classification treats that variation as the interesting fact, not an inconsistency to explain away.