Tenn. Code Ann. § 70-6-107: Grand juries

(a) The grand juries of the several counties have and possess inquisitorial powers to inquire with respect to the different offenses mentioned in this title that are punishable by a fine of more than fifty dollars ($50.00), or by imprisonment.

(b) It is the duty of the different judges of the criminal and circuit courts having jurisdiction of such matters to charge the provisions of this title to the grand juries of the different counties at each term of court in the respective counties.