Section 39 of the Capital Acquisitions Tax Act, 1976, is hereby amended by the substitution of the following subsection for subsection (7):

"(7) The Commissioners, in making any assessment, correcting assessment or additional assessment, otherwise than from a return or an additional return which is satisfactory to them, shall make an assessment of such amount of tax as, to the best of their knowledge, information (including information received from a member of the Garda Síochána) and belief, ought to be charged, levied and paid:

Provided that, where an assessment raised under this section is based, in whole or in part, or directly or indirectly, on information received from a member of the Garda Síochána, the said member's source of the said information shall not, without the express permission in writing of a member of the Garda Síochána not below the rank of Chief Superintendent, be revealed in any correspondence or communication in relation to the assessment or on the hearing or rehearing of an appeal against the assessment.".