Accusations that the Moriarty tribunal was adding one and one and getting 20 were made by Mr Denis O'Brien at yesterday's sitting.
During several sharp exchanges with Mr John Coughlan SC, for the tribunal, Mr O'Brien said he gave certain information to the tribunal because he knew "the way the tribunal would think. They would say: one and one is equal to 20, and that, I felt, was dangerous."
"Is that your understanding of how the tribunal conducts its business?" Mr Coughlan asked.
"Sometimes that could be the impression that I get as I come through the door here," Mr O'Brien replied. He said questioning could be very adversarial.
He earlier suggested that Mr Coughlan was "playing to the gallery" and was asked by the tribunal chairman, Mr Justice Moriarty, to stop making inappropriate accusations.
"Accusations such as accusing Mr Coughlan of turning around and playing to the gallery are particularly inappropriate, and I won't put up with it," Mr Justice Moriarty told Mr O'Brien.
"Well, it's not nice for me either," Mr O'Brien replied. He said it appeared as if Mr Coughlan wanted to signal that the unfolding evidence was "a big deal". Mr Justice Moriarty asked Mr O'Brien to please keep "the histrionic element" out of the proceedings.
Mr Coughlan accused Mr O'Brien of being facetious when he asked if, during a trawl of his accounts, he should have mentioned a bank account he opened in Rathgar when he was 12.
Mr Coughlan challenged a statement by Mr O'Brien that he had provided 80 per cent of the information on the tribunal's files while "everybody else has hidden behind privilege".
Mr Coughlan said other people had been of assistance to the tribunal, and their good names should not be taken by anybody in any wild way in the witness box.
Before Mr O'Brien began his evidence yesterday, his counsel, Mr Eoin McGonigal, complained about the "adversarial rather than inquisitorial approach" to Mr O'Brien on the previous day.
Mr Justice Moriarty said he would bear his submission in mind, but it did not seem to him that the questioning had strayed into elements that were "wrong, inappropriate or discourteous".
