Ohio Rev. Code § 2937.04
If accused does not desire counsel or, having engaged counsel, appears at the end of granted continuance, he may then raise, by motion to dismiss the affidavit or complaint, any exception thereto which could be asserted against an indictment or information by motion to quash, plea in abatement, or demurrer. Such motion may be made orally and ruled upon by the court or magistrate at the time of presentation, with minute of motion and ruling made in the journal (if a court of record) or on the docket (if a court not of record) or such motion may be presented in writing and set down for argument at later time. Where the motion attacks a defect in the record by facts extrinsic thereto, proof may be offered by testimony or affidavit.
R.C. §2937.04