Tennessee Code Title 55. Motor and Other Vehicles § 55-8-109

(a) The driver of any vehicle and the operator of any streetcar shall obey the instructions of any official traffic-control device applicable thereto placed in accordance with this chapter and chapter 10, parts 1-5 of this title, unless otherwise directed by a traffic or police officer, subject to the exceptions granted the driver of an authorized emergency vehicle in this chapter.

(c) For purposes of this section, “traffic or police officer” means every officer authorized to direct or regulate traffic or to make arrests for violations of traffic regulations or a person licensed under title 62, chapter 35, or authorized to carry a firearm pursuant to § 38-8-116(b), who is retired in good standing from being a commissioned, POST-certified law enforcement officer and who has notified the chief law enforcement officer in the jurisdiction where the retired officer will be directing or regulating traffic at least twenty-four (24) hours in advance, or as soon as possible in the event of an emergency, prior to performing traffic control functions in such jurisdiction.

(d) A violation of this section is a Class C misdemeanor.