Ind. Code § 34-33.1-1-1
(a) If the constitutionality of a state statute, ordinance, or franchise affecting the public interest is called into question in an action, suit, or proceeding in any court to which any agency, officer, or employee of the state is not a party, the court shall certify this fact to the attorney general and shall permit the attorney general to intervene on behalf of the state and present:
(b) If a party to an action bases its claim or defense on:
(2) a rule, order, requirement, or agreement issued or made under the statute or executive order;
the attorney general shall be permitted to intervene in the action.
As added by P.L.40-2010, SEC.2.