Utah Code Ann. § 59-1-304
(2) A class action that relates to a tax or fee may not be maintained in any court if a claim sought by a representative party seeking to maintain the class action arises as a result of:
(b) any of the following that requires a change in the manner in which a tax or fee is required to be collected or paid:
(iii) a decision issued by:
(3)
(a) A person may be included as a member of a class in a class action relating to a tax or fee only if the person:
(b)
(ii) The rules required by Subsection (3)(b)(i) may include rules providing for:
(4) Subject to Subsection (5), in a class action brought under this section against the state or its political subdivisions in which members of the class are awarded a refund or credit of a tax or fee by a court of competent jurisdiction, the total amount that may be recovered by members of the class may not exceed the difference between:
(5)
(a) For purposes of Subsection (4), at the discretion of the court, the court may award:
(b) Reasonable attorney fees awarded in a class action may not exceed a reasonable hourly rate for work actually performed: