Ohio Rev. Code § 4909.12
The findings of the public utilities commission made and filed under section 4909.11 of the Revised Code, when properly certified under the seal of the commission, are admissible in evidence in any action, proceeding, or hearing before the commission or any court, in which the commission, the state or any officer, department, or institution thereof, or any county, municipal corporation, or other body politic, and the public utility or railroad affected may be interested, whether arising under Chapters 4901., 4903., 4905., 4907., 4909., 4921., 4923., and 4925. of the Revised Code or otherwise. Such findings, when so introduced, shall be evidence of the facts stated in them, as of the date stated in them under conditions then existing.
R.C. § 4909.12