Ohio Rev. Code § 2943.06: Trial of issue on plea of former conviction.

If a defendant pleads a judgment of conviction, acquittal, or former jeopardy, the prosecuting attorney may reply that there is no such conviction, acquittal, or jeopardy. The issue thus made shall be tried to a jury, and on such trial the defendant must produce the record of such conviction, acquittal, or jeopardy, and prove that he is the person charged in such record, and he may also introduce other evidence to establish the identity of such offense. If the prosecuting attorney demurs to said plea and said demurrer is overruled, the prosecuting attorney may then reply to said plea.