Indiana Code Title 3. Elections § 3-10-5-30

Sec. 30. If at or about the time of submitting a constitutional amendment, Congress, either in the resolution submitting the amendment or by statute, prescribes the manner in which the conventions are to be constituted and does not except from the resolution or statute states that have provided for conventions, this chapter is inoperative and the convention shall be constituted and operate as the resolution or statute directs.  Each public official of this state who is authorized or directed by the resolution or statute to take action to constitute a convention for this state shall act in accordance with it as if acting under a statute of this state.