Although we colloquially know it as the Mahon tribunal, and previously knew it as the Flood tribunal, the full name for the inquiry before which Bertie Ahern gave evidence this week is the Tribunal of Inquiry into Certain Planning Matters and Payments, writes Noel Whelan.
Unlike the Moriarty tribunal, which inquired into payments to Charles Haughey and is still inquiring into payments to Michael Lowry, the Mahon tribunal is not an inquiry into payments to politicians per se. Neither is it a tribunal of inquiry into payments to Bertie Ahern or into his personal finances.
It is worth reiterating that point at this stage because now that the Taoiseach's evidence at the tribunal has failed to live up to the dramatic billing which some gave it, many commentators have moved on to suggesting that the defining moment will come when the tribunal publishes its report, which they confidently predict will be damaging for him.
The central matter that the Mahon tribunal can deal with in its report is the effect, if any, that payments to Bertie Ahern did or did not have (or were or were intended to have) on the planning process.
There are only two people who are publicly known to have made allegations to the tribunal that Ahern received a bribe from a developer. One of those was Denis "Starry" O'Brien, who alleged he had handed over thousands of pounds to Ahern on behalf of the property developer Owen O'Callaghan. O'Brien's allegation made the front page in the Sunday Business Postin April, 2000.
A private inquiry conducted by the planning tribunal quickly established that O'Brien's allegation had no basis in fact. Subsequently, a Circuit Court ruled that the allegation was untrue in every respect.
The other person to allege to the planning tribunal that Ahern received a bribe from a developer was Tom Gilmartin. Gilmartin has claimed that Owen O'Callaghan once told him he had given payments of IR£50,000 and IR£30,000 to Ahern. It is this Gilmartin allegation that has led to Ahern's involvement in the current Quarryvale II module of the tribunal's work. Both Ahern and O'Callaghan have strenuously denied Gilmartin's claim.
As part of its investigation into whether Gilmartin's allegation is true, the tribunal began an investigation into Ahern's finances. During this investigation, the tribunal identified five large movements of money into Ahern's accounts or accounts held for him.
The tribunal, however, is not examining these lodgements in themselves, but is doing so to rule in or rule out the possibility that they are monies from O'Callaghan.
If Ahern had given a single, clear explanation of when and how these payments came to him and if he had the paperwork to support this explanation, the tribunal could have concluded its investigation into his finances privately. However, he has not been able to do so. This may be because for much of the time covered by this inquiry, he lived an all-cash lifestyle.
It may be because things are complicated by the fact that at times some monies were held or administered in his name by his then partner. It may be because he is embarrassed or politically exposed by his acceptance of large cash payments as loans or donations from businessmen. It may be because he resents having to give his personal financial details to the tribunal - a resentment that can only have been exacerbated when some payment details became public while he was still dealing with the tribunal in private.
It may all be because Ahern's natural disposition is to be circumspect and selective in revealing information. We do not really know and will probably never know but, whatever the reason, Ahern could not prove in correspondence or in a private interview with the tribunal that nothing touching on its terms of reference arose from these payments.
That is why the tribunal has - quite legitimately - sought to further investigate the nature and sources of these payments and to do so at public hearings.
However, in its report, the tribunal will not and indeed cannot decisively rule on whether or not the Taoiseach's explanation of these lodgements is accurate. Its function will not be to rule on whether Ahern's story about the payments is credible but rather whether there is any basis to Gilmartin's allegation. The latter question arises from the tribunal's terms of reference; the former does not.
Those hoping for adverse findings against Ahern on this point are likely to be disappointed. To date, the only "evidence" to support Gilmartin's allegation of a bribe is that of Gilmartin himself and he has proved an unreliable witness in public and private testimony to the tribunal.
Ahern's account of these payments has been confusing, contradictory and incomplete, but that of itself does not substantiate Gilmartin's charge against him. This week, the tribunal's previous chairman, Feargus Flood, offered the view that unless some new evidence emerged, the tribunal would not make an adverse finding against Ahern. It will be hard on the basis of what they have heard to date for the current tribunal judges to come to any other conclusion. Gilmartin's claim is unproven and so Ahern stands innocent of the allegation made.
Others were hoping that the tribunal report will rule that Ahern has impeded or obstructed it or failed to comply with its orders. The pace and extent of Ahern's co-operation with the tribunal has been far from ideal, but it has not been so deficient as to meet the relatively high bar required for a ruling that it was obstructive. The tribunal's chairman has already indicated a charge of non-compliance is not being made.
This payments controversy did not fatally wound Ahern politically last autumn or during the election campaign and it is not fatally wounding him now. The publication of the tribunal report itself will not fatally wound him either. There is still every reason to believe he will get to go at a time of his own choosing.