For effective administration, supervision, and regulation of public utilities, communications carriers, and common or contract carriers, the administrator, at his or her discretion, may designate examiners, investigators, hearing officers, or one or more agents of the division to make investigations and conduct hearings. In conducting investigations and hearings, the administrator and every person designated therefor by him or her shall be vested with all the powers conferred on the chairperson of the commission by § 39-1-13. Upon completion of his or her investigation and hearing, the person hearing or investigating shall file his or her recommended decision and findings in writing with the administrator; and the decision and findings, when approved by the administrator, shall have the same force and effect as a decision and findings by the administrator. The administrator may, however, at his or her discretion, upon considering the evidence in the matter at issue and the written recommended decision as filed by the hearing officer, agent, examiner, or investigator, decide the matter in hearing or under investigation him or herself, and in such case, the decision of the administrator with his or her findings shall become effective when signed and filed by him or her.