All information derived from any examination of the books and accounts made pursuant to this chapter by the assessor, or anyone acting for him or representing him, shall be deemed to be and held as confidential communications not to be communicated to any other person by the person making such examination, or anyone to whom the knowledge of such examination or facts therein disclosed shall come, except when it becomes necessary as a part of the performance of the public duty of such person to disclose the same in any proceeding affecting the validity of said assessment or taxation, or for the prosecution for perjury of the person required to make the statement mentioned in this chapter. Any person or officer making such disclosure or violating such confidence, except as herein provided, shall be deemed guilty of a felony, and upon conviction thereof shall be removed from office and punished as in case of other felonies.