(a) The commission shall adopt any rules necessary to carry out its powers and duties under this code and other laws of this state.
(b) The commission shall adopt reasonable procedural rules to be followed in a commission hearing. The executive director may recommend to the commission for its consideration any rules that he considers necessary.

(c) Rules shall be adopted in the manner provided by Chapter 2001, Government Code. As provided by that Act, the commission must adopt rules when adopting, repealing, or amending any agency statement of general applicability that interprets or prescribes law or policy or describes the procedure or practice requirements of an agency. The commission shall follow its own rules as adopted until it changes them in accordance with that Act.
(d) The commission shall include as a part of each rule the commission adopts, and each proposed rule for adoption after the effective date of this subsection, a citation to the statute that grants the specific regulatory authority under which the rule is justified and a citation of the specific regulatory authority that will be exercised. If no specific statutory authority exists and the agency is depending on this section, citation of this section, or § 5.102 or 5.013, is sufficient. A rule adopted in violation of this subsection is void.