Today AIB executives will finally make an appearance before the Dail Committee of Public Accounts. After weeks of evidence from its competitors, the Central Bank and the Revenue Commissioners, the committee will be seeking comprehensive answers as to why the State's largest bank facilitated bogus non-resident accounts and failed to pay DIRT arrears to the Revenue.
This morning AIB's former head of internal audit, Mr Tony Spollen, will face the committee's questions. He was the author of the leaked internal memo which estimated that AIB could have a potential DIRT liability of £100 million arising from the bogus non-resident accounts which triggered the inquiry.
He can expect to be vigorously questioned on how he arrived at that figure and whether he still stands over it. AIB disputes the figure, suggesting that a liability of between £25 million and £35 million is more realistic.
The bank began to reclassify bogus non-resident accounts as eligible for DIRT payments in 1991. Initially it had estimated the total amount held in bogus non-resident accounts at up to £600 million, but this was later reduced to £500 million. This makes AIB the biggest offender in opening bogus accounts over the 12-year period being investigated by the committee.
In preparing a defence, the bank's current and former executives will no doubt have paid close attention to what Bank of Ireland and ACCBank, in particular, have told the committee about their bogus accounts and their dealings with the Revenue Commissioners on DIRT.
Judging by the questioning over the past few weeks, each executive will be expected to tell the committee when they became aware of the problem and what they did about it.
Two former AIB chairmen, Mr Peter Sutherland and Mr Jim Culleton, and the current chairman, Mr Lochlainn Quinn, will have to detail the extent of the information which filtered through to the boardroom about these accounts.
AIB's chief executive, Mr Tom Mulcahy, will have to deal with the situation since he took office in 1992, although much of the questioning is likely to be directed at his predecessor, Mr Gerry Scanlan, who became chief executive in 1985.
PricewaterhouseCoopers, AIB's auditors, will also have to outline the extent of its knowledge of bogus non-resident accounts.
Other key witnesses will be AIB officials who dealt with group taxation matters, specifically Mr Jimmy O'Mahony, Ms Deirdre Fullen and Dr Donal de Buitleir.
They will be asked to explain how they came to believe that they had secured an amnesty from the Revenue Commissioners in 1991. AIB insists that the Revenue agreed that it was not required to collect and pay DIRT retrospectively for bogus non-resident accounts up to June 1991.
The Revenue officials who attended this meeting have already strongly denied that any such deal was ever brokered with AIB. But the Revenue also accepts that it failed to follow this up and collect a cheque for arrears from the bank.
AIB will have been heartened to hear that the State-owned ACCBank believed that it was offered a similar deal a year later. Again this has been rejected by the Revenue.
So far, the committee has managed to establish that neither of the two banks ever got confirmation of an amnesty in writing from the Revenue. Yesterday AIB's former deputy managing director, Mr Billy Moore, explained that the bank's tax advisers, Ernst & Young, who had attended the meeting with the Revenue, did not believe that it was necessary to clarify the position.
AIB similarly was happy to accept a verbal agreement from the Revenue at the time.
The committee will be trying to tease out whether some informal agreement was indeed reached between the Revenue and the two banks and, if this was the case, whether it should be honoured.