Former Labour Sligo/Leitrim TD Declan Bree has been found to be in breach of party rules for criticising Sligo Borough Council colleagues who opposed an itinerant halting site in the town.
However, the party's complaints committee has not disciplined Cllr Bree, who was Sligo's mayor up to a few months ago, although it said that his actions had been "extremely serious".
The controversy erupted last February after he clashed with two Labour Sligo Borough Council colleagues, Cllr Veronica Cawley and Cllr Jimmy McGarry when they voted against the council's Traveller accommodation programme.
Since then, Mr Bree and the Labour leader, Pat Rabbitte have engaged in increasingly bitter exchanges, with Mr Rabbitte going so far as to allege that Mr Bree had stopped the construction of a halting site in his ward in the town - a charge sharply refuted by Mr Bree.
Last Saturday, Mr Bree left the complaints hearing in protest, alleging that Labour's general secretary Mike Allen had "flagrantly abused natural justice".
In its ruling, seen by The Irish Times, Labour's complaints committee said it upheld the complaint lodged by the secretary of the Sligo/Leitrim Constituency Council, Peigin Doyle, because his actions were "injurious" to Labour's interests. However, the complaints committee insisted that the disciplinary hearing had nothing to do with the merits of Sligo's Traveller accommodation programme. "The decision to uphold the complaint is not an adjudication on which councillors made the better decision in relation to their vote on the Traveller accommodation programme.
"The Labour Party has been and remains committed to equal treatment for Travellers and the provision of adequate and appropriate accommodation for the Traveller community.
"It expects all public representatives to pursue this objective, using their political judgment accordingly. We are satisfied that Cllr Cawley and Cllr McGarry fulfilled this commitment," it said.
The five-strong disciplinary committee said Mr Bree's public criticisms were unfair: "The criticisms he made were entirely unsubstantiated based on the extensive evidence that the committee has heard."