Performance of free work or work compensated at less than minimum wage for a public or charitable purpose, by any person under the supervision of the department of corrections, shall not be deemed employment within the meaning of the provisions of chapter 288. Any county, city, person, organization, or agency charged with the supervision of such free work or who benefits from its performance shall be immune from any suit by the offender or any person deriving a cause of action from him if such cause of action arises from such supervision or performance, except for negligence or an intentional tort.
§ 217.437, RSMo