Colorado constitution
Article XX
Section 2

The officers of the city and county of Denver shall be such as by appointment or election may be provided for by the charter; and the jurisdiction, term of office, duties and qualifications of all such officers shall be such as in the charter may be provided; but the charter shall designate the officers who shall, respectively, perform the acts and duties required of county officers to be done by the constitution or by the general law, as far as applicable. If any officer of said city and county of Denver shall receive any compensation whatever, he or she shall receive the same as a stated salary, the amount of which shall be fixed by the charter, or, in the case of officers not in the classified civil service, by ordinance within limits fixed by the charter; provided, however, no elected officer shall receive any increase or decrease in compensation under any ordinance passed during the term for which he was elected.