81-9-305. Power to administer oaths, subpoena witnesses, and receive evidence. Hearings held under 81-9-301 through 81-9-306 for either revocation of licenses or to restrain operation shall be held by the department, and the department or its agent may administer oaths, subpoena witnesses, and receive evidence in order to carry out 81-9-301 through 81-9-306.