A senior AIB executive denied the bank's tax department had to support the existence of a DIRT amnesty because it would be blamed when the "crisis" surfaced in 1991.
Dr Donal de Buitleir, former head of group taxation, said there was no "culture of blame" in AIB. It was not going to be the subject of a "witch hunt" and he rejected the idea that he and two other executives in the tax department were engaged in "some sort of nefarious conspiracy because we feared for our personal position".
He was questioned by counsel for the Revenue Commissioners, Mr Eoghan Fitzsimons SC, who repeatedly pressed him on why the bank was able to sort out its DIRT problem within two months in 1991 when it could not do so for the previous five years.
Dr de Buitleir said he was absolutely confident that there was an agreement and the Revenue had to choose between "absolute utter incompetence and negligence" or an agreement.
Mr Fitzsimons suggested that the tax department had to support the existence of an agreement "come what may otherwise there was going to be an awful lot of explaining for you to do".
The bank executive denied the bank's share price would have "crumbled" if the bank had had to pay out on its DIRT liability, put by the bank's current chairman at a maximum potential of £35 million.
Mr Fitzsimons put it that the board would have had an inquiry to find out who was to blame if the share price fell following the necessary profits warning to the Stock Exchange. There would have to be a warning because of the liability.
Dr de Buitleir said there would have been an investigation but if the Revenue pursued whatever the figure was, back to 1986, "the bank would have collected the money from the customers because it was the customers' liability".
Mr Fitzsimons said that in the year when a "very serious matter" was being considered, Dr de Buitleir, the tax expert, had written just one memo which was a "cog" of a summary drawn up by another executive, Ms Deirdre Fullen, of the meeting in 1991 with the Revenue at which the agreement was considered.
He replied that it was a logistical issue for branches rather than a technical tax matter and there was no need for him to be writing big memos.
Dr de Buitleir said he prepared no memo and it did not occur to him to seek advice. However, "I still am absolutely confident that what the Revenue proposed, what we understood they proposed, in February 1991 was well within their powers of care and management".
He was encouraged by the evidence of the former Revenue chairman, Mr Cathal Mac Domhnaill, who said that even the chairman would have the authority to write off "fully quantified" tax in the case of a solvent company.
Dr de Buitleir said the Revenue did not fully quantify the tax because it could not have actually proceeded the way it did.
The Revenue's counsel repeatedly pressed Dr de Buitleir about why he, as "the head of the taxation department and a supposed taxation expert", had not taken appropriate steps before 1991 to ensure AIB complied with its DIRT self-assessment obligations.
The former head of group taxation insisted that the tax department had taken considerable steps but it had 16 people and it could not "police" this itself. The job of doing it had to be done at individual branches.
He denied he was suggesting that the bank did the Revenue or the people of Ireland a "favour" when it got its house in order between February and March 1991.
