The returns made by appraisers and all data otherwise gathered by the state tax commissioner, shall be considered privileged communications and shall not be inspected or copied by any person other than the executor, administrator or a beneficiary entitled by the will or by intestate law to share in the estate, or the duly authorized attorney of the executor, administrator or beneficiary.
Nothing in this section shall be construed to prohibit the use of such returns or data in legal proceedings involving the assessment, collection or abatement of taxes provided for by the various inheritance tax statutes of this state.