Questioning in the planning tribunal had moved far beyond the inquiry's remit, according to its chairman, Mr Justice Flood.
As far as he was concerned counsel were "wandering aimlessly in the desert" and beyond what the inquiry had been established to investigate, the payment of money to the former minister, Mr Ray Burke.
The inquiry chairman made his remarks after cross-examination of Mr John Lane, a chartered accountant, by a number of counsel. Mr Lane was being questioned about a row over the way JMSE was being run in the 1980s.
Mr Justice Flood said he was obliged to inquire into the payment of "a sum of money to an individual and the history and sequence of events leading to that payment".
He called on counsel for Mr James Gogarty, Mr Frank Callanan, SC, to end the cross-examination of Mr Lane and said he was strongly of the view that the tribunal had gone "far, far too wide" in its deliberations and well outside what they were there to investigate.
Mr Callanan said that counsel for JMSE, Mr Dan Herbert SC, had introduced reports which the witness had never seen and now he was seeking to shut down an examination of that.
Mr Justice Flood said the question about Mr Gogarty's credibility had got out of control.