In the discharge of its duties and the enforcement of its jurisdiction under this title, the commission shall:
(2) hear and determine complaints;
(3) require the attendance of witnesses and pay their expenses out of funds provided for that purpose;
(4) obtain the issuance of writs and process which may be necessary for the enforcement of its orders; and
(5) punish for contempt or disobedience of its orders in the manner provided for the district courts.
Tex. Nat. Res. Code § 81.053
Acts 1977, 65th Leg., p. 2510, ch. 871, art. I, Sec. 1, eff. 9/1/1977.