In those counties under the County Uniform Highway Law, a very strict conflict of interest statute applies.  The statute, T.C.A. § 54‑7‑203(a), provides:

Neither the chief administrative officer, county highway commissioner, member of the county governing body nor any employee of the county road department shall be financially interested in or have any personal interest, either directly or indirectly, in the purchase of any supplies, machinery, materials, equipment or contractual services for the department or system of roads for the county, nor in any firm, corporation, partnership, association or individual selling or furnishing such machinery, equipment, supplies and materials.