Tennessee Code Title 4. State Government § 4-7-112

(a) The commissioner of safety is charged with the proper administration of this part, and may make such rules and regulations relating thereto as may be necessary.

(b) The expenses of carrying out this part, including the compensation of the members of the Tennessee highway patrol, and their necessary expenses incurred in the performance of their duties, shall be paid out of the motor vehicle fund; provided, that such expenses and compensation shall not exceed ten percent (10%) of such fund per annum; and provided further, that only the net amount of the motor vehicle fund shall be subject to allocation between the department of transportation and the various counties.