Tennessee Code Title 16. Courts § 16-15-735

(a) In cases or controversies arising in a court of general sessions, if a defendant feels that the defendant is either not at fault or that another person is also at fault, the defendant is to notify the opposing party or parties and the clerk of the court in writing forty-eight (48) hours prior to the scheduled date of the hearing of the names, if known, of the other person or persons at fault. If the defendant fails to so notify, the plaintiff shall be entitled to a continuance.

(b) After receiving notice that additional defendants may exist, the clerk of the court shall notify the plaintiff of this fact. The clerk shall automatically continue the hearing for thirty (30) days following notification to the plaintiff that additional defendants exist so the plaintiff can issue service and amend the warrant to include any new defendants.