Indiana Code Title 36. Local Government § 36-7-5.1-6

Sec. 6. After a commission is established, it shall exclusively exercise all the planning, zoning, platting, and land use policy authority for real property in the joint district.  The joint district commission has exclusive authority, subject to section 7 of this chapter, to adopt a zoning ordinance or a subdivision control ordinance, or both.  Any planning, zoning, platting, or land use functions exercised by any other unit or entity in the joint district shall cease.  Except as provided in section 7 of this chapter, an action of the commission is final and does not require a reference to or an approval by a county or municipal legislative body.