When Bertie Ahern looked me in the eye and said, "Yes", what he really meant was "No".
Imagine my shock yesterday when the Taoiseach entirely contradicted the answer he gave me to a pretty straightforward question only eight days ago.
Back from his visit to Africa, Mr Ahern continued his Third-World aid theme by opening the new Irish Aid Volunteering and Information Centre -- a worthy addition to O'Connell Street.
As it was the first opportunity to question the Taoiseach in over a month, there was a large media contingent present.
Last year, Mr Ahern became the 'Tetchy Taoiseach'. Since the New Year, though, he's been in pretty fair form.
In keeping with his 'Lovebomb Bertie' demeanour in Africa, Mr Ahern was in a good mood.
He dealt with whatever questions were put to him, on the value for money of the new centre, on the stability of the economy and on the turmoil in the international stock markets.
Standing right in front of him, at the back of the press scrum, when the subject moved on to his personal finances, I put a question to him on his tax affairs.
Nothing major, just a clarification, and if anything I regarded it as a rhetorical question, as indications had been given by Mr Ahern that his tax affairs could not be dealt with until after the Mahon Tribunal had reported.
"Taoiseach, just in relation to this complaint that has now gone into the Public Office Commission, can I ask you a question on your Tax Clearance Certificate issues. Have the Revenue Commissioners informed your advisers that they will have to wait for the Mahon Tribunal to report back before finalising your own situation?"
Mr Ahern looked directly at me and nodded his head twice. But he didn't say anything audible so I prompted him again, by saying, "Yes?".
In fairness, his response was pretty clear.
"Yes. That, that, that... the issue here is very, very simple. In tax law, the application certificate and the tax clearance are the same in law.
"And the position taken by the Revenue is that they can't finalise it until Mahon's work is finished. So, I mean, that's fine by me. I have no difficulty with that, I have no difficulty with the Revenue position."
Mr Ahern responded to another question on the matter and in total he used the words "finished" or "finalised" six times in relation to Mahon's impact on his dealings with the Revenue.
Even by the Taoiseach's regular standards, it was crystal clear.
Until the Mahon Tribunal had reported, the Revenue Commissioners couldn't sort out whether or not he had a tax liability.
Until his tax affairs were cleared up, the State ethics watchdog couldn't adjudicate on a complaint on the tax clearance certificate he produced in 2002.
Then yesterday the story changed -- completely.
Mr Ahern's response to Labour Party leader Eamon Gilmore's quite similar question on his contacts with the Revenue Commissioners was quite astonishing.
"It is not correct, and if I said so, I was not correct -- I cannot recall if I said it, but I did not say, or if I did, I did not mean to say it -- that these issues could not be dealt with until the end of the Mahon Tribunal," the Taoiseach said.
In other words, the complete opposite to what he said only eight days previously.
Of course, this isn't the first time Mr Ahern has performed a quite startling reverse on his tax affairs. On the record of the Dail in September 2006, he said he didn't have a tax liability and he had consulted with the "tax authorities".
Just 11 days before the General Election, he revealed to the 'Sunday Independent' he was in contact with the Revenue Commissioners and had made a provisional payment to cover any possible tax liability.
When I pointed out the inconsistency to Mr Ahern later that day at a press briefing at Blanchardstown Shopping Centre, he wouldn't say how much he had paid over.
"I'm not going to get into that. I mean, I paid a full declaration and I think I'll get most of that back, if not it all."
Although it has since emerged that Mr Ahern has put €70,000 on account with the Revenue to cover any possible liability, the final bill is actually irrelevant.
You can't be half pregnant. Mr Ahern either owes tax or he doesn't.
Full stop. End of story.
Mr Ahern seems to think there is no difference between not having a tax bill and having just a small tax bill.
The reason Mr Ahern's tax status is so important is perfectly simple.
He was Minister for Finance when he received the dig-out payments. He was responsible for the collection and distribution of taxes at the time. He was responsible for tax and budgetary policy at the time. He was responsible for the Revenue Commissioners at the time.
Forget about the origin of the funding for a moment.
If Mr Ahern actually had a tax bill from the time when he was Minister for Finance, all the rest of this affair pales into insignificance.
Nobody can categorically say Mr Ahern actually does have a tax bill, but the reality is the Taoiseach can't say he doesn't.
And that's why this is so serious and Mr Ahern deserves to be questioned about it and give straight answers.