In accordance with the laws governing the state civil service, the commissioner shall employ and, with the approval of the Department of Finance, fix the compensation of such personnel as the commissioner needs to discharge properly the duties imposed upon the commissioner by law, including legal counsel to act as the attorney for the commissioner in actions or proceedings brought by or against the commissioner under or pursuant to any provision of any law under the commissioner`s jurisdiction, or in which the commissioner joins or intervenes as to a matter within the commissioner`s jurisdiction, as a friend of the court or otherwise, and stenographic reporters to take and transcribe the testimony in any formal hearing or investigation before the commissioner or before a person authorized by the commissioner. The personnel of the Department of Corporations shall perform such duties as the commissioner assigns to them. Such employees as the commissioner designates by rule or order shall, within 15 days after their appointments, take and subscribe to the constitutional oath of office and file it in the office of the Secretary of State.