Mr Justice Flood has told Mr Oliver Barry he has given "unsatisfactory" evidence to the tribunal. He said he would refer the matter to the High Court if necessary.
"I do require openness and frankness, and when I find it isn't there I will take the necessary steps . . . to refer the matter to the High Court," he said.
Mr Justice Flood was referring to the former Century Radio director's "remarkable lack of clarity" regarding certain banking transactions.
"I would invite you to very carefully consider your position, because I want to be convinced of the truth of what you're telling me," Judge Flood added.
He said it was desirable that citizens co-operate so the tribunal did "not have to take a shoehorn to extract from the heels of the individual concerned," he said.
He adjourned Mr Barry's evidence until he was able to give more information to the tribunal about the accounts.
Mr Barry was unable to give explanations about money transferred from accounts in Barclays Bank on the Isle of Man.
Mr Patrick Hanratty SC, for the tribunal, also asked Mr Barry why he had not previously told the tribunal about the existence of a bank account in Cork which was used by his concert promotion company, Quality Artistes Management (QAM).
Another account in the Isle of Man was also not disclosed, Mr Hanratty said.
"It seems to be a case of `catch me if you can', but you're not volunteering the information," he said.
He added: "The tribunal is confronted with a blanket assertion by Mr Barry that he himself has no records of any kind whatsoever of any of these accounts in the Isle of Man, and we are asked to examine that.
"Not one single sheet of paper, not one cheque counterfoil, no statements that would have been sent to him at the time, no correspondence of any kind between himself and the bank."
Counsel for Mr Barry said the Cork bank account was in the name of Ms Maeve McManus, a QAM director, and Mr Barry was not able to obtain information about it without her consent.
He also said Barclays Bank only kept documents relating to transactions made in the last five years and would therefore not have information on accounts Mr Hanratty had asked about.
He said Mr Barry had taken his inquiries into the bank accounts as far as he could.