Tenn. Code Ann. § 40-23-109

The judge or clerk of the court may, by warrant in writing, empower the sheriff charged with the conveyance of the convict, in all counties and places through which the sheriff may pass with the prisoner, to summon or impress such and so many persons, not exceeding two (2) for each convict, except as otherwise provided in this chapter, and the conveyances or modes of conveyance as shall be necessary for the safe conveyance of the prisoner, which warrant the sheriff is required to execute, and to the sheriff's commands in virtue thereof all persons are to pay due obedience.