Tex. Utilities Code § 58.026: CONSUMER COMPLAINTS REGARDING TARIFFS.

(a) This chapter does not restrict:

(1) a consumer's right to complain to the commission about the application of an ambiguous tariff; or

(2) the commission's right to determine:

(A) the proper application of that tariff; or

(B) the proper rate if that tariff does not apply.

(b) This section does not permit the commission to:

(1) lower a tariff rate except as specifically provided by this title;

(2) change the commission's interpretation of a tariff; or

(3) extend the application of a tariff to a new class of customers.

Acts 1997, 75th Leg., ch. 166, Sec. 1, eff. Sept. 1, 1997.