Utah Code § 54-7-21
The commission shall see that the provisions of the Constitution and statutes of this state affecting public utilities, the enforcement of which is not specifically vested in some other officer or tribunal, are enforced and obeyed, and that violations thereof are promptly prosecuted and penalties due the state therefor recovered and collected; and to this end it may sue in the name of the state of Utah. Upon request of the commission, it shall be the duty of the attorney general to aid in any investigation, hearing or trial under the provisions of this title and to institute and prosecute actions or proceedings for the enforcement of the provisions of the Constitution and statutes of this state affecting public utilities and for the punishment of all violations thereof.
Utah Code § 54-7-21