1987 Constitution of the Philippines
Section 18. The Congress shall enact an organic act for each autonomous region with the assistance and participation of the regional consultative commission composed of representatives appointed by the President from a list of nominees from multi-sectoral bodies. The organic act shall define the basic structure of government for the region consisting of the executive department and legislative assembly, both of which shall be elective and representative of the constituent political units. The organic acts shall likewise provide for special courts with personal, family, and property law jurisdiction consistent with the provisions of this Constitution and national laws.
The creation of the autonomous region shall be effective when approved by majority of the votes cast by the constituent units in a plebiscite called for the purpose, provided that only provinces, cities, and geographic areas voting favorably in such plebiscite shall be included in the autonomous region.