Johor is a constitutional monarchy. It was the first state in Malaysia which adopted the constitutional monarchy system, and its laws are stated in "Undang-undang Tubuh Negeri Johor" (Johor State Establishment Constitution), written by Sultan Abu Bakar. The constitutional head of Johor is the Sultan. This position can only be passed down and held by a member of the Johor Royal Family, who is descended from Sultan Abu Bakar. The State's Sultan since 1981 has been Sultan Iskandar Al-Haj.