Colo. Rev. Stat. § 40-7-101
It is the duty of the commission to see that the constitution and statutes of this state affecting public utilities, and persons subject to article 10.1 or 10.5 of this title, 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 are recovered and collected, and to this end it may sue in the name of the people of the state of Colorado. Upon the request of the commission, the attorney general or the district attorney acting for the proper county or city and county shall aid in any investigation, hearing, or trial had under articles 1 to 7 of this title and institute and prosecute actions or proceedings for the enforcement of the constitution and statutes of this state affecting public utilities and persons subject to article 10.1 or 10.5 of this title and for the punishment of all violations thereof.
C.R.S. § 40-7-101