Tenn. Code Ann. § 9-2-103: Receipts required

Each state, county and municipal official who receives any sum or sums in such official's capacity shall issue to the payer thereof a receipt and shall retain a duplicate thereof in the office of such official; provided, that this provision for official receipts shall not apply to the payment of funds from one department or division of the state government to another such department or division. Any system now in use shall be acceptable if approved by the comptroller of the treasury.