Tennessee traffic laws do make reference to the use of green lights by funeral escort motorcycles. Other funeral home escort vehicles must use amber lights (§ 55-9-402), but you can see a combination of amber and green in actual use.
This is the only reference I could find in the Tennessee law about green lights.
Tennessee Code 55-8-183 Funeral processions.
( B) Motorcycle escorts of properly identified funeral processions may:
(3) Notwithstanding § 55-9-402 or any other law to the contrary, install a green strobe flashing light system of a type approved by the sheriff of the county in which the motorcycle is to be operated; provided, that the system is deactivated at all times the motorcycle is not escorting a properly identified funeral procession.
But we see security vehicles patrolling parking lots using green lights as well.