Ind. Code § 8-1-2-60

Sec. 60. Notice of the time and place for such hearing shall be given to the public utility and to such other interested persons as the commission shall deem necessary, as provided in section 56 of this chapter, and thereafter proceedings shall be had and conducted in reference to the matter investigated in like manner as though complaint had been filed with the commission relative to the matter investigated, and the same order or orders may be made in reference thereto as if such investigation had been made on complaint.