Sec. 20. (a) All lawful actions of the commission, including all rules and operating procedures adopted by the commission, are binding upon the compacting states.
(b) All agreements between the commission and the compacting states are binding in accordance with the terms of the agreements.
(c) Upon the request of a party to a conflict over the meaning or interpretation of commission actions and upon a majority vote of the compacting states, the commission may issue advisory opinions regarding the meaning or interpretation in dispute.
(d) Any provision of this compact that violates the Constitution of the State of Indiana is ineffective in Indiana.