The Supreme Court said that while it had held the powers of the Moriarty tribunal were valid under the Constitution, its powers must be construed within the constitutional framework and in particular with regard to fair procedures.
While the tribunal was entitled to conduct the preliminary stage of its investigations in private and make such orders as it considered necessary for the purpose of its functions, that did not mean it was not, in the making of such orders, obliged to follow fair procedures.
Fair procedures required that the persons likely to be affected by the making of such orders be given notice of the intention to make such an order and an opportunity before the order is made to make representations with regard to it.
Such representations could include a submission that the orders were not necessary for the purpose and functions of the tribunal and were too wide and extensive, having regard to its terms of reference and other relevant matters.
The court said such a procedure was not adopted. It said the High Court was correct in holding the tribunal did not act in accordance with fair procedures or constitutional justice in making its orders.
That failure was not remedied by the insertion into the orders of a provision giving affected persons the right to apply to the tribunal to vary or discharge the orders, the Chief Justice said.
This was particularly so in the present case where there were no exceptional circumstances, such as a legitimate fear of destruction of documents if prior notice was given.
Mr Justice Hamilton said each of the appellants was entitled to the benefit of fair procedures, and the court was satisfied the High Court was wrong in differentiating between the rights of Mr Haughey and the other members of his family.
He said the High Court had refused, as a matter of discretion, to quash the orders saying the tribunal had acted bona fide, the Haugheys had since had an opportunity of airing their legitimate complaints, and it would be pointless to declare void the orders and force the tribunal to embark on a new and cumbersome procedure before it would be able to get back whatever bank accounts it now had.
The Chief Justice said while that approach by the High Court "may enjoy the attractiveness of being pragmatic and, indeed, realistic", it did not have regard to the seriousness of the Haugheys' right to fair procedures and the court's obligation to defend and vindicate the constitutional rights of the citizen.
"The vindication of such rights requires that the impugned orders of discovery made by the tribunal other than in accordance with fair procedures be quashed and that the tribunal be deprived of the benefit of such order and the court will so order."
He said the quashing of the orders did not preclude the tribunal from making similar orders in the future provided they were made in accordance with fair procedures.