Tennessee Code Title 39. Criminal Offenses § 39-16-612

(a) A person commits an offense who intentionally approaches, within twenty-five feet (25′), a law enforcement officer after the officer has ordered the person to stop approaching or to retreat and the officer is lawfully engaged in the execution of official duties involving:

(b) It is an affirmative defense to a violation of subsection (a) that the lawful order was not received or understood by the person and was not capable of being received or understood under the conditions and circumstances that existed at the time of the issuance of the order.

(c) A violation of subsection (a) is a Class B misdemeanor.