A unanimous Supreme Court decision yesterday has cleared the way for the inspectors investigating the affairs of National Irish Bank (NIB) to begin interviewing the bank's employees. The court upheld a High Court decision that staff and former staff must answer the inspectors' questions.

However, the court also decided that any confession by a bank official obtained by the inspectors as a result of their powers under Section 10 of the Companies Act would not, in general, be admissible at a subsequent criminal trial of that official unless, in any particular case, the trial judge was satisfied the confession was voluntary. Section 10 provides that an inspector may certify to the High Court a refusal to answer questions or disclose documents by a company official.

The inspectors - accountant Mr Tom Grace and Mr John Blayney SC - had planned to begin interviewing NIB employees last May but waited until legal proceedings regarding the interviewing process were concluded yesterday with the Supreme Court decision. In the interim, the inspectors have proceeded with other aspects of their investigation.

On the application of the Tanaiste and Minister for Enterprise, Trade and Employment, Ms Harney, the High Court last March appointed the inspectors to investigate and report on the affairs of NIB.

Their brief relates to improper charging of interest and fees to accounts of customers between 1988 and March 1998; improper removal of funds from accounts of customers in the same period; steps and action taken by NIB, its directors, officers, servants or agents in relation to charging such fees or interest or removal of funds without consent of the account holders and their actions arising from the issues when discovered.

The investigation is also looking into the manner in which NIB's books, records and accounts reflected the identity of the person or persons responsible for or aware of any of those practices and whether other unlawful or improper practices existed in NIB which served to encourage evasion of Revenue or other obligations on the part of the bank or third parties.

The inspectors had intended to commence interviewing employees on May 28th, 1998. However, after solicitors for some existing and retired employees wrote to the inspectors concerning their clients' rights to refuse to answer questions on grounds of possible self incrimination, the inspectors applied to the High Court for directions regarding the interviewing process.

The proceedings on behalf of the staff were taken by a nominated representative, Mr John O'Reilly, manager of the NIB branch, Patrick Street, Limerick. The High Court ultimately ruled that the employees should answer the inspectors' questions.

Yesterday's 41-page Supreme Court judgment dealt at length with the "right to silence" and with previous court decisions regarding that right. The classic decision on the right to silence at common law and the Free State Constitution was in a 1936 case (State, McCarthy v Lennon) it stated.

In that case, a man was arrested and initially refused to answer questions.

When the implications of his refusal were drawn to his attention, he made a statement, which was admitted at his trial, despite objections. It was the only substantive evidence against him and he was convicted. The Supreme Court of the Irish Free State decided by a 2-1 vote that the statement had been properly admitted.

Mr Justice Barrington, giving the Supreme Court judgment yesterday, said that, if there were grounds for believing there was malpractice or illegality in the operation of the banking system, it was essential, in the public interest, that the public authorities should have power to find out what was going on.

It appeared the powers given to the inspectors under Section 10 of the Companies Act 1990 were no greater than the public interest required. Their meaning was clear and they passed the proportionality test. Accordingly, it appeared that interviewees were not entitled to refuse to answer questions properly posed to them by the inspectors.

He said the decision in the 1936 case was not a safe guide for any person seeking to establish the rights of the citizen under the Irish Constitution.

It appeared to him that the better opinion was that a trial in due course of law required that any confession admitted against an accused person in a criminal trial should be a voluntary one.

It also appeared that any trial at which an alleged confession other than a voluntary one were admitted in evidence against an accused would not be a trial in due course of law within the meaning of Article 38 of the Constitution and that it was immaterial whether the compulsion or inducement used to extract the confession came from the executive or legislature.

The better interpretation of Section 18 of the Companies Act which deals with evidence uncovered in the course of questioning by inspectors, in light of the Constitution, was that it did not authorise the admission of forced or involuntary confessions against an accused in a criminal trial. It could be stated as a general principle that a confession, to be admissible at a criminal trial, must be voluntary.

The issue of whether a confession was voluntary or not must, in every case in which the matter was disputed, be a question to be decided in the first instance by the trial judge.

Mr Justice Barrington said the question had arisen of what would be the position of evidence discovered by the inspectors as a result of information uncovered by them following the exercise of their powers under Section 10. It was proper to make clear that what was objectionable under Article 38 of the Constitution was compelling a person to confess and then convicting them on the basis of their compelled confession.

In the final analysis, it would be for a trial judge to decide whether, in all the circumstances of the case, it would be just or fair to admit any particular piece of evidence, including any evidence obtained as a result or in consequence of the compelled confession.

The presiding judge, Mr Justice O'Flaherty, as well as Mr Justice Lynch, Mr Justice Murphy and Mr Justice Barron, agreed with the judgment of Mr Justice Barrington. Each side - the inspectors and the staff - must bear their own costs of the Supreme Court appeal. The High Court costs had been borne by the inspectors.