(a) Except in accordance with proper judicial order or as otherwise provided by law, it is unlawful for the commissioner, other officer, employee, or agent, or any former officer, employee, or agent to divulge or make known in any manner the amount of income or any particulars set forth or disclosed in any report or return required under the law of this state or any return or return information required by the Internal Revenue Code when the information or return is received from the Internal Revenue Service or submitted by the taxpayer as provided by the laws of this state. Nothing contained in this Code section shall be construed to prohibit the print or electronic publication of statistics so presented as to prevent the identification of particular reports or returns and the items thereof, or the inspection by the Attorney General or other legal representative of the state, or use as evidence, of the report or return of a taxpayer in the event of any action or proceeding involving any tax liability of the taxpayer. Reports and returns shall be preserved for three years and thereafter until the commissioner orders them to be destroyed.

(b) The commissioner may permit the commissioner of internal revenue of the United States, the proper officer of any state imposing an income tax similar to that imposed by this chapter, or the authorized representative of either such officer to inspect the income tax returns of any taxpayer, or may furnish to the officer or his authorized representative an abstract of the return of income of any taxpayer or supply him with information concerning any item of income contained in any return or disclosed by the report of any investigation of the income or return of income of any taxpayer. The permission shall be granted or the information shall be furnished to the officer or his representative only if:

(1) The request is only for state tax information including federal tax information required by the state to be filed by the taxpayer with his state return;

(2) The requested information will be used solely for tax purposes;

(3) The requesting state has a confidentiality statute which complies with the requirements of Section 6103(p)(8) of the Internal Revenue Code; and

(4) The statutes of the United States or of such other state, as the case may be, grant substantially similar privileges to the proper officer of this state charged with the administration of this chapter.

(c) The commissioner may permit the disclosure of inventories, depreciable assets, accumulated depreciation, and book value of depreciable assets to local tax authorities in this state to be used solely for ad valorem tax purposes, provided that the furnishing of the information is not prohibited by Section 6103 of the Internal Revenue Code; and provided, further, that the furnishing of the information to the local tax authorities shall not be deemed to change the confidential character of the information, and any persons receiving the information pursuant to this subsection shall be subject to Code Section 48-7-61, relating to the sanctions to be imposed for the unauthorized disclosure of confidential material.

(d) This Code section shall not be construed to prohibit persons or groups of persons other than employees of the department from having access to tax information where necessary to conduct research commissioned by the department or where necessary in connection with the processing, storage, transmission, and reproduction of such tax information; the programming, maintenance, repair, testing, and procurement of equipment; and the providing of other services for purposes of tax administration. Any such access shall be pursuant to a written agreement with the department providing for the handling, permitted uses, and destruction of such tax information, requiring security clearance checks for such persons or groups of persons similar to those required of employees of the department, and including such other terms and conditions as the department may require to protect the confidentiality of the tax information to be disclosed. Any person who divulges or makes known any tax information obtained under this subsection shall be subject to the same civil and criminal penalties as those provided for divulgence of information by employees of the department.

(e) Notwithstanding any other law, this Code section shall remain in full force and effect unless specific reference is made in such other law to this Code section and to the disclosure of income tax information contained in any report or return required under this Code section.