Michael Moriarty cut a lonely figure in Dublin Castle last Thursday. He sat in his elevated position looking out on the tribunal of inquiry which bears his name. He has been sitting there for 13 years. The first public hearing of the inquiry took place on 31 October 1997.

Standing in the body of the room, asking questions on behalf of the inquiry, was Michael McDowell, which should have been some comfort to the chairman. McDowell is a highly capable barrister. He is new to the inquiry, but he had some knowledge of the matter at hand from previous work he had done. McDowell was retained to examine a crucial witness into the inquiry of the awarding of the highly lucrative mobile phone licence in 1995. Michael Lowry was the minister for communications at the time. He has been exposed as a cheat and a liar. The tribunal is examining whether the licence, won by Denis O'Brien's Esat company, was awarded properly.

Proceedings across the Liffey in the Four Courts may have given Moriarty pause for thought. Billionaires O'Brien and Dermot Desmond were bringing proceedings objecting to McDowell's involvement, citing conflicts of interest from the lawyer's previous roles as attorney general and politician. Anything that might slow down the inquiry from moving to a swift conclusion must have been of concern to the chairman.

Of far greater concern though, if not outright discomfort, was the evidence emanating from the man in the witness box at the Castle. Michael Andersen is a Danish academic who acted as a consultant in the competition to award the mobile phone licence. If he had come to give his evidence eight years ago, it might have saved the state up to €100m in tribunal costs. But he refused because he smelt a rat and didn't want anything to do with it.

On Thursday, Andersen said it was his firm belief that the inquiry has been biased since soon after it began investigating the matter at hand. He spoke of meetings he had with members of the tribunal's legal team where he detected hostility.

"In numerous instances, the tribunal has carried their work along on the basis that A3 (a company called Persona, which was also bidding for the licence) was the winner of some part of the evaluation."

He emphasised this point again. "I think it's part of the working hypothesis of this tribunal that A3 should have been the winner, so therefore, in my view, over a number of examples, A3 has been declared by this tribunal, and private meetings by the legal team, as the winner of this quantitative studies."

If his evidence is accepted, it infers there was a ready-up. Somebody, somewhere decided that the awarding of the licence was not undertaken properly and what was required was to unearth the evidence to support this theory. As a way of doing business, it mirrors the habit of some police officers to determine early on who did it and then look for the evidence.

The evidence in this case is highly circumstantial. A money trail of sorts leading from interests associated with O'Brien to those close to Lowry has been uncovered. The trail began sometime after the awarding of the licence, not before. A series of transactions have not been explained satisfactorily. There was no direct transfer of funds between the parties. But any inquiry making findings on the balance of probabilities might well conclude that money passed, or was intended to pass, between them.

Even if that were the case, it does not make it a bribe, or inducement. For such a payment to be made it would have to be shown that something was done in which Lowry abused his power to present O'Brien with an advantage. According to Andersen, the tribunal has been working backwards from the position that O'Brien's company didn't win on merit, and therefore must have been handed some advantage. It is a damning accusation that goes to the heart of the tribunal's credibility.

In November 2008, the tribunal issued provisional findings. O'Brien has let it be known that extensive findings were made against him. If such findings were confirmed, it would be a devastating blow to his reputation. He has long maintained that he is being set up by the inquiry. As a result, he has invested huge resources in putting his case into the public domain, creating a blizzard of spin around the whole inquiry.

A number of officials in the Department of Communications are concerned at the provisional findings. On Tuesday, a lawyer for the state let it be known that any findings against the state would be challenged in court.

What's left of Lowry's reputation is also at stake. He is a cheat and a liar, but he doesn't deserve to be branded corrupt unless sufficient evidence is produced to that effect. He says he can no longer afford representation. On Thursday, he drifted in at 12.30am and sat at the tables reserved for lawyers before leaving for the Clonmel Races. Coincidentally, his vote in the Dáil is propping up the government, which in turn represents the state, which warned the tribunal about negative findings.

Two of the tribunal's three senior counsel weren't present on Thursday. John Coughlan is on sick leave. He has earned over €9m from his tribunal work. Jerry Healy, who has pocketed a similar fee, wasn't in the room. Neither was Jacqueline O'Brien, who has clocked up close to €6.5m.

Moriarty must be wondering how he has arrived at this station. He has already admitted making two significant mistakes in this element of the tribunal, both of which arguably disadvantaged the positions of O'Brien and Lowry.

He entered the inquiry with a solid reputation, which was enhanced in the early, difficult years when Charlie Haughey's finances were the subject matter. Right now, his stewardship is under intense scrutiny, and it isn't bearing up well. The tribunal continues to cost a fortune.

On Friday, the High Court gave McDowell the go-ahead to continue with his examination of Andersen. The previous day, the former justice minister had for a while reverted to the persona that informed his political character in years past. "I don't quite understand the angry tone and temper of Mr Michael McDowell," Andersen said at one point. "I have come here to try to assist the tribunal to understand what the evaluation is about."

He has done that, and brought with him plenty of food for the chairman's thoughts. Right now, the tribunal looks like it could end its days as a scandal.