(a)  It is unlawful, except in proceedings before a court of competent jurisdiction or to collect the taxes or enforce the penalties provided by chapters 18 and 19 of this title, for the tax administrator or any person having an administrative duty under those chapters to make known in any manner whatever the business affairs, operations, or information obtained by an investigation of records and equipment of any retailer or any other person visited or examined in the discharge of official duty, or the amount or source of income, profits, losses, expenditures, or any particular, stated or disclosed in any return, or to permit any return or copy or any book containing any abstract or particulars to be seen or examined by any person. The tax administrator may authorize examination of his or her records and the returns filed with the administrator by the tax authorities of another state or of the federal government if a reciprocal arrangement exists.

(b)  Nothing in this section shall be construed to prevent the disclosure or publication of statistical or other information where the identity of individual taxpayers is not made known.

(c)  The tax administrator may make available to the taxing officials of the various towns and cities of the state, for tax purposes only, any information that the administrator considers proper concerning state residents registering motor vehicles in other states.