royal decrees are the other main source of law; but are referred to as "regulations" rather than "laws" because they are subordinate to the sharia. royal decrees supplement sharia in areas such as labor, commercial and corporate law. additionally, traditional tribal law and custom remain significant. extra-sharia government tribunals usually handle disputes relating to specific royal decrees. final appeal from both sharia courts and government tribunals is to the king and all courts and tribunals follow sharia rules of evidence and procedure.