Tenn. Code § 33-6-503
No defendant may be judicially committed under this part unless two (2) licensed physicians; one (1) licensed physician and one (1) licensed psychologist qualified under § 33-6-427(a); or one (1) licensed physician and one (1) qualified advanced practice provider as defined in § 33-6-407(a), who is not in a collaborating agreement with the licensed physician who signed the other certificate required by this section, file in the commitment proceeding certificates of need for care and treatment certifying that the defendant satisfies the requirements of § 33-6-502(1)-(4) and showing the factual foundation for the conclusions on each item. No defendant who is a child under sixteen (16) years of age may be judicially committed under this part unless one (1) of the certificates is filed by a physician, psychologist, or qualified advanced practice provider with experience with children.
T.C.A. § 33-6-503