Former taoiseach John Bruton has denied trying to impose a whip on Fine Gael members of Dublin County Council in the early 1990s.
However, Mr Bruton agreed he made a "strong request" as party leader to councillors to reach agreement on planning matters before they came up before the council.
He denied warning councillors who failed to vote with the majority of their colleagues that they would have to leave the party and said no sanctions were envisaged if they failed to follow his advice.
Mr Bruton, who is now head of the European Commission delegation in Washington, said he asked to meet the 19 Fine Gael members on Dublin County Council in September 1993, following controversy over the way the county development plan was being finalised.
In particular, he was concerned that party councillors were voting "against one another" rather than reaching a group position.
"My view was that this was not good from any point of view."
Other more disciplined parties were having a greater impact on the future shape of Co Dublin; it was common knowledge, for example, that Fianna Fáil imposed a whip.
Mr Bruton said he was more concerned about the general image of the party than the specific content of the development plan. Ultimately, he was aware that councillors were exercising a quasi-judicial role and it wasn't possible to impose sanctions.
If council members wanted to impose a whip on themselves that would be for them to do it; it wasn't for him to impose sanctions. Ultimately, he said, he was unsuccessful and the councillors continued to vote in different ways.
He pointed out that an earlier Fine Gael leader, Garret FitzGerald had also failed to impose unity on the councillors.
The tribunal ruled out questions to Mr Bruton on the running of the Fine Gael payments inquiry in 2000, saying this was likely to result in a further sub-module into the conduct of this private inquiry.
Lawyers for former Fine Gael councillor Cathal Boland had earlier contended that Mr Bruton should have been called to give evidence to the party inquiry, even though he was not a Dublin political representative.
Mr Boland declined to co- operate with the inquiry, saying he was bound by a requirement of confidentiality to the tribunal.
Developer Phil Monahan sent Fine Gael a £2,500 cheque made out to "John Bruton Fine Gael leader" during the 1992 election campaign, and sent the party a £3,000 cheque in 1997, the tribunal heard.
Mr Bruton said he did not know Mr Monahan and would not have been directly involved.
Later, lawyers for Fianna Fáil Senator Don Lydon called on the tribunal to make an early decision on the value of evidence given by PR consultant Bill O'Herlihy about their client.
Séamus Ó Tuathail SC, for Mr Lydon, described as a "fairytale" Mr O'Herlihy's allegation that a Monarch Properties executive told him the politician had been paid £100,000 to distribute to other councillors who would support the rezoning of the company's land at Cherrywood.
He said the allegation was an unsupported piece of malicious gossip that was grossly prejudicial to his client.
Mr Lydon was facing re-election next year and his career was in the balance.
