Ohio Rev. Code § 4113.08: Minors.

In all actions described in section 4113.03 of the Revised Code, where a minor employee has been employed or retained in employment contrary to the laws of this state or of the United States, such employee shall not be held to have been guilty of contributory negligence, nor held to have assumed any of the risks of such employment. The employer may show by way of defense any fraud or misrepresentation made by such employee.