1. (1) A respondent shall serve on the petitioner and file with the Commission a responsive pleading within 30 days after the service of a complaint or initial petition, except where otherwise provided by statute, these rules, or an order of the Commission.

2. (2) Every defense, in law or fact, to an order or notice commencing a contested case or to an initial petition, shall be asserted in an answer, except that the following defenses may, at the option of the respondent, be made by motion in writing:

   1. (a) Lack of jurisdiction over the subject matter;
   2. (b) Lack of jurisdiction over the person;
   3. (c) Insufficiency of notice;
   4. (d) Insufficiency of service of the order, notice or petition;
   5. (e) Failure to state a claim upon which relief can be granted; or
   6. (f) Failure to join an indispensable party.
3. (3) A motion raising any defenses in (2) may be made before filing an answer, or combined with the answer. Such motions shall be disposed of before a hearing on the merits.
4. (4) If the initial petition is so vague or ambiguous that the respondent cannot reasonably be required to frame a response, the respondent may move for a more definite statement before filing an answer. Such a motion shall identify the defects complained of and the details desired. If the motion is granted, a more definite statement shall be furnished by a date- certain fixed in the order granting the motion.
5. (5) Upon motion made by any party within ten days after the service of a petition or answer upon that party, or on its own initiative, the Commission or Hearing Officer may order stricken from any petition, answer, or motion to dismiss, any insufficient defense or irrelevant, immaterial, impertinent or scandalous matter.
6. (6) A respondent waives all defenses listed in (2) not presented either by motion, answer, or any amendment, except that lack of jurisdiction over the subject matter may be raised at any time. The defenses enumerated in subparagraphs (2)(b), (c), and (d) shall not be raised by amendment.

Authority: T.C.A. §§ 65-2-102, 65-4-101, and 65-4-104. Administrative History: Original rule filed June 30, 2000; effective September 13, 2000. Administrative changes made to this chapter on April 27, 2018 pursuant to Public Chapter 94 of 2017; “Tennessee Regulatory Authority” references were changed to “Tennessee Public Utility Commission,” “Authority” references were changed to “Commission,” “Authority Director” references were changed to “Commissioner,” and “Chief” references were changed to “Director.” Amendments filed August 11, 2025; effective November 9, 2025.