(a) Except in accordance with proper judicial order or as otherwise required by law, it is unlawful for the commissioner and any deputy, agent, clerk or other officer or employee, to make known in any manner the amount of income or any particular set forth in any report or return required under this chapter, nor shall the information contained in any report filed by any taxpayer under the requirements of this chapter be used by the state or any county or municipality for the purpose of imposing any other or different tax on any such taxpayer; provided, that nothing in this section shall be construed to prohibit the publication of statistics so classified as to prevent the identification of particular reports or returns by legal representatives of the state in any suit or suits for the collection of the tax or any part of the tax or for the penalty and interest imposed by this chapter.

(b) A violation of any of this section is a Class A misdemeanor.

(c) The commissioner of revenue may permit the commissioner of the internal revenue service, or the proper officer of any state imposing a tax similar to that imposed by this chapter, or the authorized representative of either such officer, to inspect the tax return of any corporation, or may furnish to such officer or to the officer's authorized representative an abstract of the return of any corporation or supply the officer or representative with information concerning any item contained in any return; but such permission shall be granted or such information furnished to such officer or representative only if the statutes or regulations of the United States or of such other state, as the case may be, grant substantially similar privileges to the governor or the proper officers of this state charged with the administration of this chapter.

(d) Municipal and county assessors of property shall be permitted by the commissioner and any deputy, agent, clerk, or other officer or employee, to inspect the tax return of any corporation and, upon request of such municipal or county assessors of property, the commissioner and any deputy, agent, clerk, or other officer or employee, shall be required to furnish to such assessor of property or the assessor of property's authorized representative an abstract of the return of any corporation or supply the assessor of property or representative with information concerning any item contained in any return.