The commissioner may make investigations necessary for the proper administration of this part. For the purpose of making investigations, the commissioner shall have inquisitorial powers and shall be empowered to subpoena witnesses and examine them under oath; provided, that all testimony, documents and other evidence obtained by the commissioner pursuant to this section shall be absolutely privileged and shall not be admissible as evidence in any private civil proceeding. Notwithstanding this section, the adjuster may request and obtain from the department a copy of any charges brought against the adjuster, or if no charges have been filed, a written notice of the alleged violation.