Tennessee Code Title 4. State Government § 4-3-604

(a) The commissioner may make such investigations as the commissioner may deem necessary to the performance of the commissioner's duties, and to that end the commissioner shall have the same power as a judge of the court of general sessions to administer oaths and to enforce the attendance and testimony of witnesses and the production of books and papers.

(b) The commissioner shall keep a record of such investigations, stating the time, place, character or subject, witnesses summoned and examined, and the commissioner's conclusions.

(c) In matters involving the conduct of an officer, a stenographic report of the evidence shall be taken and a copy thereof with all documents introduced kept on file at the office of the department.

(d) The fees of witnesses for attendance and travel shall be the same as in the circuit court, but no officer or employee of the institution under investigation shall be entitled to such fees.

(e) Any judge of the circuit court, either in term time or in vacation, upon application of the commissioner, may compel the attendance of witnesses, the production of books or papers and the giving of testimony before the commissioner, by a judgment for contempt or otherwise, in the same manner as in cases before a circuit court.