Tenn. Code Ann. § 40-25-111: Payment for transporting prisoners - Limitation on charges

(a) The sheriff or other officer, conveying an inmate to the penitentiary, shall make out an account in writing, stating the number of miles on the usual route from the place of conviction to the penitentiary, the number of guards necessarily employed to ensure the safe conveyance of the inmate, and the distance each of the guards may have traveled, and make oath to the truth of the account before the warden of the penitentiary, or any judge, who shall certify the fact.

(b) Upon presentation of the account thus sworn to and certified, the director of accounts shall issue a warrant for the amount, as in other cases, if satisfied of the correctness of the account.

(c) It is the duty of the sheriff to carry to the penitentiary, at the same time, all inmates in the sheriff's custody, at that time sentenced to the penitentiary, and the sheriff shall not be entitled to charge for more than one (1) trip.