In any hearing the commission may employ a special agent or examiner, who may administer oaths, examine witnesses consistent with the Judicial Code of Conduct, and receive evidence in any locality which the commission, having regard to the public convenience and the proper discharge of its functions and duties, may designate. The testimony and evidence so taken or received shall have the same force and effect as if taken or received by the commission or any one or more of the commissioners as provided in § 58-9-1010. But any hearing involving rates of any telephone utility shall be held before a majority of the full commission.