Then at the dinner's end, another of their number, a younger chap, rises to address the gathering. He speaks at some length on the subject of the Irish economy, there in the middle of the restaurant, while you and the other diners are striving for a quiet evening.

His voice drones over the soft piped music. You are tempted to call the management. If somebody told you that this chap was in fact the minister for finance of the Irish Republic, giving an impromptu briefing to a bunch of multi-millionaires, you would have fallen off your seat.

You would have been totally flummoxed if you spotted what went down later. The party repairs to the hotel bar. Later, Kilroe approaches the minister and presents him with an envelope bulging with �50 notes. There is around �8,000 in the envelope, worth at least 20,000 in today's money. Nice work if you can get it. Fortunately, these Irish multimillionaires carry bundles of cash on their person, enough to cough up an average of �400 a skull.

All very strange but, we are assured, all very true.

So it went during Bertie's wild years. On Friday, the planning tribunal heard a reconstruction of the night Ahern got lucky in Manchester back in 1994. The account he gave differed from earlier accounts to both the tribunal and the public. There is no record of the handover of a wad of cash from business interests to a finance minister. Tim Kilroe is dead. Only one other businessman has a recollection of the night. And the only records available appear to call into question whether the event ever happened. All very strange but, we are assured, all very true.

The Manchester bundle of cash best sums up the problems Bertie Ahern is having in relation to his finances. Over a two-year period, from 1993 to 1995, we now know his bank accounts processed cash sums of �50,000, �22,500, �24,838 . . . which represented a sterling sum of either �8,000 or �25,000 . . . and more sterling packets of �30,000, �20,000 and �10,000.

There could be another ten or 20 grand in there also, depending on how much was recycled. In today's money, up to 500,000 went through his accounts.

All we have is his word There is no record of where all this cash came from. All we have is Ahern's word. And after two days giving evidence in the tribunal, his word is looking decidedly shaky.

When Manchester first surfaced last September, Ahern assured us that a key motivation for the boys to slip him the eight grand was his "personal circumstances". This was a reference to the financial fallout from the legal termination of his marriage. He first mentioned this in his tearful interview with Bryan Dobson. On 3 October, he told the Dail that the contribution was made "because of my personal circumstances".

Since then, we have learned that in October 1994 Ahern's finances were in rude health. He had around �30,000 in a savings account and another �39,000 in cash, the latter being the proceeds of two friendly dig-outs. He had more money available to him than most of us will ever have in our lives.

No surprise then that his story had changed by last Friday. There was no tearful account of his personal circumstances. Instead, he suggested that the few bob was given to him in appreciation for the speech and "detailed question and answer session" he had endured after his dinner. Of course, he had been wearing his Bertie Joe Public hat, rather than his ministerial garb, a distinction that is difficult to understand in a minister for finance talking about the national economy.

There was no passing of a hat. "These are serious people, " Ahern told the tribunal in explaining that they wouldn't stoop to passing a hat.

Instead, Kilroe handed him an envelope bulging with around 160 �50 notes. "He said he wanted to make a contribution, " Ahern told the tribunal. "I asked him was it political. He said no, it was personal."

Changing stories This makes a refreshing change at a tribunal.

Before now, any time the personal/political issue came up, the witness . . . Liam Lawlor, Ray Burke, any number of councillors . . . insisted that a contribution was political, lest there be any suggestion they took money for their personal use. Ahern also makes the distinction, but he says it was personal rather than political, which is just as well because it went into his personal bank account.

The group didn't hire a function room so there is no record of the dinner. Last autumn, Bertie was sure it was in September 1994. He has changed his story. Now he says it could have been April or May at the end of the football season. If somebody was attempting to find evidence that the event actually occurred, this change of story muddies the waters.

Ahern says many of the businessmen were "good friends" of his.

Yet only one of them, a John Kennedy, is in a position to confirm the event. A member of the 'Drumcondra mafia', senator Tony Kett, was also there.

What's the betting he didn't see money changing hands?

The minister for finance didn't count his stash that night. He came home after the weekend and put the money in his safe. He spoke to Kilroe later that week on the phone. He didn't send an acknowledgement note. "It was �8,000, no big deal, " he said on Friday, a curious observation for a man who originally claimed he was on his uppers at the time. There is no record of a handover of the cash.

On 11 October 1994, he lodged the takings in his bank, AIB at O'Connell Street. This lodgement was combined with �16,500 from a local digout to give a total lodgement that day of �24,838.49. In two reports compiled for him by accountant Des Peelo and in a private interview with the tribunal last April, Ahern confirmed that the lodgement was composed solely of exactly those two elements. He was certain about it. Now, he has changed his story.

The tribunal discovered that the lodgement couldn't have happened as Ahern said because it would have involved the bank taking in English pence, which it won't do. In addition, on 11 October the sum of �24,838.49 represented exactly an Irish equivalent of �25,000 if one of the available exchange rates on the day is used. On the very same day, the branch took in �27,491.45 worth of sterling. Its average takings are around �2,200. On Ahern's lodgement slip, there is no note making the distinction between the sterling and punt elements of the lodgement, as there usually would be. Either a whopping coincidence occurred, or Ahern actually lodged stg�25,000 that day.

Naturally, Ahern disputes the records. His ever-changing story now is that the lodgement could have included more sterling added to that which he got in Manchester, or there might be some subtracted. There could be more Irish punts in the mix beyond the �16,500 or there could be less. His new story makes an analysis of the lodgement more difficult.

Strengthened by his popularity He also maintains that the incorrect exchange rate would have been applied if it was stg�25,000.

He doesn't believe that it could have been an error or that, heaven help us, he was "screwed" by a teller applying a lower rate to squeeze a few extra bob for the bank.

If banks didn't have a reputation for playing fast and loose with exchange rates . . . as recent foreign exchange scandals suggest they do . . . and if human error could be eliminated, he might have a point. If this was the only whopping coincidence in his financial narrative, his contention might have more credibility.

The sceptical observer could reasonably ask a few pertinent questions: did Manchester occur at all? Did Ahern actually lodge stg�25,000 as the records seem to suggest? If so, from whom did he get that money and why? Is Bertie Ahern hiding something big?

Just before his last appearance at the tribunal in 2004, Ahern's counsel suggested to Tom Gilmartin that he was a "shifty" witness.

Gilmartin has made numerous allegations . . .

many of them blatantly spurious . . . against the taoiseach. Ahern himself told the tribunal that Gilmartin changed his story several times. Three years on, the taoiseach might be accused of throwing stones in a glasshouse.

Another fabled witness to the tribunal came to mind during Ahern's evidence last Thursday. The late Liam Lawlor was jailed three times for failing to cooperate with the inquiry. It took from October 2004 to April of this year for the tribunal to get a full account of Ahern's finances out of him. In 2005, he swore an affidavit which omitted mention of a beneficial account of his, in Celia Larkin's name, in which was lodged �50,000. Was he trying to hide something?

Like Lawlor, Ahern provided voluminous material for the inquiry, but omitted the specific nuggets that were requested. Unlike Lawlor, Ahern eventually coughed up the details.

Two days in the witness box last week did a lot of damage to the taoiseach's credibility. If much more is revealed during next week's hearing, it will be difficult to see how he retains any moral authority to impose standards in public office.

Lesser politicians would be gone by now. He is fortified by his popularity, his record of public service and the manner in which his people have spun the story thus far.

The narrative of Ahern's finances, as told by him, is bizarre and grubby. That alone wouldn't be a hanging offence in somebody of his status.

The growing problem is the credibility of his version of events. Is he telling the truth? Is the mounting evidence to be believed? Where exactly did he get all that money?