Tennessee Code Title 9. Public Finances § 9-3-209

(a) When suits are instituted by the county mayor or by the comptroller of the treasury as herein provided, the fee to be allowed and paid the attorney for such attorney's services shall be fixed by the county mayor where the suit is instituted by direction of the county mayor, but the same shall be approved by the comptroller of the treasury; and, where suits are instituted by direction of the comptroller of the treasury upon the failure of the county mayor, such attorney's fees shall be fixed by the comptroller of the treasury, with the approval of the governor.

(b) No attorney's fees shall accrue against the state or county unless they are collected by the attorney from penalties of delinquents.