Ohio Revised Code Title XLIX. Public Utilities § 4905.26

Upon complaint in writing against any public utility by any person, firm, or corporation, or upon the initiative or complaint of the public utilities commission, that any rate, fare, charge, toll, rental, schedule, classification, or service, or any joint rate, fare, charge, toll, rental, schedule, classification, or service rendered, charged, demanded, exacted, or proposed to be rendered, charged, demanded, or exacted, is in any respect unjust, unreasonable, unjustly discriminatory, unjustly preferential, or in violation of law, or that any regulation, measurement, or practice affecting or relating to any service furnished by the public utility, or in connection with such service, is, or will be, in any respect unreasonable, unjust, insufficient, unjustly discriminatory, or unjustly preferential, or that any service is, or will be, inadequate or cannot be obtained, and, upon complaint of a public utility as to any matter affecting its own product or service, if it appears that reasonable grounds for complaint are stated, the commission shall fix a time for hearing and shall notify complainants and the public utility thereof. The notice shall be served not less than fifteen days before hearing and shall state the matters complained of. The commission may adjourn such hearing from time to time.

The parties to the complaint shall be entitled to be heard, represented by counsel, and to have process to enforce the attendance of witnesses.

This section does not apply to matters governed by Chapter 4913. of the Revised Code.