Analysis: After a week of impressive direct evidence to the Mahon tribunal, Mr Tom Gilmartin is coming under serious pressure in cross-examination. Paul Cullen reports.
The present hearings of the planning tribunal may continue for many months and even years, but their political significance will be determined by the evidence heard here and now.
At stake are the reputations of, on the one hand, the tribunal's "star" witness and, on the other, the Taoiseach, Mr Ahern. The tribunal won't have the luxury of accepting both men's versions of what happened in the late 1980s, when Mr Gilmartin was canvassing political support for his building projects.
It was clear from Mr Gilmartin's direct evidence that he ran into serious problems when trying to advance these projects. It was equally clear that he told a remarkable number and variety of people - politicians, officials, gardaí, other businessmen - about these problems, including the demands that he cough up money in return for the removal of "roadblocks" or obstacles to his progress.
We know, too, for certain that he paid £50,000 to the then minister for environment, Mr Pádraig Flynn, in May/June 1989, even if the circumstances and motive behind this payment remain in dispute.
However, the problems with Mr Gilmartin's story were evident from the moment Mr Conor Maguire SC, for the Taoiseach, started asking questions.
These include: a lack of documentary evidence; a lack of supporting witnesses; questions about the dates he has provided for key events; inconsistencies between the various accounts he has given; and questions about his motivation.
Mr Gilmartin says he met Charles Haughey and six of his ministers, including Mr Ahern, on February 1st or 2nd, 1989. Nothing much turns on the meeting itself, but outside he says he was subjected to a £5 million extortion demand. Understandably, any politician who wanted to preserve his reputation would want to distance himself from such goings-on.
Mr Maguire yesterday served up an alibi for the Taoiseach for February 1st, the date recorded for the meeting in Mr Gilmartin's diary (though not for February 2nd).
But he went much further, by casting doubt on the authenticity of the developer's diary entries and questioning his knowledge of the internal passageways in Leinster House Mr Gilmartin would have taken to get to the claimed meeting.
He also asked how could Mr Haughey have known in February 1989 that his son Seán was going to be Lord Mayor, as claimed, when this didn't happen for another five months. Equally, how could Mr Ray MacSharry have known he was going to be EU commissioner when he is alleged to have met Mr Gilmartin in 1987, 11 months before he was actually appointed?
So Mr Maguire has succeeded in casting considerable doubt on the date for the alleged meeting. However, as Judge Alan Mahon pointed out, the question of whether a meeting took place at all is a separate one. Mr Gilmartin has struggled with dates and it could be that he has got this one wrong as well.
However, the manner with which he has dealt with these probing questions has not been edifying. Constantly on the defensive, Mr Gilmartin has railed against everyone - politicians, business contacts, journalists. Allegations and insults have been flung about with gay abandon. Mr Gilmartin is always right and everyone else is wrong. Even denying being embittered made him sound embittered.
Take away the allegation about the Leinster House meeting and you are still left with a compelling account of political sleaze. This would also have the effect of leaving Bertie Ahern in the clear, thereby defusing the tribunal's impact on today's politics.
Ironically, given the mauling he received during the two days of Mr Maguire's cross-examination, Mr Gilmartin finished on a high. Through his lawyers, the Taoiseach seriously misjudged the tribunal and the public gallery by pulling a rabbit - a 26-year-old Cavan court case - out of his hat. The result was a reprimand from Judge Mahon and five rounds of applause for the witness.
The final verdict on Mr Gilmartin's stories may well depend on the evidence of supporting characters to whom he told his story at the time.
However, it is true that Mr Ahern's lawyers have punched a large hole in the developer's story, which many others will be eager to follow.
The tribunal resumes on Friday.