Ohio Revised Code Title VII. Municipal Corporations § 733.581

If the village solicitor or city director of law, upon the written request of any taxpayer of the municipal corporation, makes any application provided for by section 733.56, 733.57, or 733.58 of the Revised Code, the taxpayer may be named as a party defendant and if so named shall have the right to assist in presenting all issues of law and fact to the court in order that a full and complete adjudication of the controversy may be had.

In any civil action or proceeding involving the public interest the court shall grant the application of any person to intervene if the court believes that the public interest will be better protected or justice will be furthered.