Tennessee Code Title 68. Health, Safety and Environmental Protection § 68-102-131

Every person, summoned and testifying before the commissioner, the commissioner's deputies or assistants, shall receive from the funds for the maintenance of the department, on the certificate of the commissioner, for witness fees and mileage, such sum or sums as provided for witnesses testifying in the circuit courts of this state, and officers serving subpoenas and rendering other services to the commissioner shall be paid as for like services in such courts.