When so authorized by the city legislative authority, the judges of the city may appoint one or more municipal court commissioners. A commissioner must be a registered voter of the city, and shall hold office at the pleasure of the appointing judges. A person appointed as a commissioner authorized to hear or dispose of cases must be a lawyer who is admitted to the practice of law in the state of Washington. A commissioner has such power, authority, and jurisdiction in criminal and civil matters as the appointing judges possess and may prescribe.