Ala. Code § 16-18A-11
While any of the revenue bonds issued by the authority remain outstanding, the powers, duties or existence of the authority or of any of its officers shall not be diminished or impaired in any manner that will affect adversely the interest and rights of the holders of such revenue bonds. The provisions of this chapter shall be for the benefit of the state, the authority and the holders of any such revenue bonds, and, upon the issuance of the revenue bonds as herein provided, such provisions shall constitute a contract with the holders of such revenue bonds. The provisions of any bond resolution, indenture or trust agreement shall be a contract with every holder of such revenue bonds and the duties of the authority under any such bond resolution, indenture or trust agreement shall be enforceable by any bondholder by mandamus or other appropriate suit, action or proceeding at law or in equity.
Ala. Code § 16-18A-11 (1975)