The TUI congress overwhelmingly rejected any involvement in proposed new school inspection schemes and condemned its leadership for disobeying its instructions on the issue.
An amended motion "emphatically" rejected the new Whole School Evaluation (WSE) scheme and instructed the union's executive to resist pressure from the Department of Education to introduce it.
It directed TUI members not to take part in Whole School Evaluation or Whole School Inspection and in any pilot project connected with it.
The motion condemned the executive for "disobeying" specific instructions from last year's congress not to enter a Department WSE pilot project in 12 schools.
Speakers queued up to attack school inspection and the union's leadership in the most heated debate seen at this year's congress.
Mr Jim McCarthy, Dublin, said the Department wanted to present WSE as "more benign" than British inspection procedures which had "devastated teachers' morale". He urged delegates "not be be fooled by this", warning that WSE would greatly increase teachers' workloads and lead to a diversion of public funds from where it was really needed in the classroom.
Mr Brian McGivern, Donegal, said it had been an unedifying spectacle to see senior officers of the union exhorting TUI members in Co Dublin to break a directive of congress by taking part in the WSE pilot project.
Mr John O'Donovan, Clare, said the union leadership was being dishonest, both towards congress and the Department of Education, since it was probable that the pilot project would be judged a success and then the TUI would have to drop out because the union congress would have voted to have nothing to do with WSE.
Mr Eddie Taggart, Donegal, said whatever euphemism was used for the new kind of inspection, it would take priority over everything else and would lead to greatly increased teacher workloads, stress levels and absenteeism.
Mr John McDonagh, Kildare, said that despite assurances from the Minister of State, Mr Willie O'Dea, that they had nothing to fear, once WSE started it would finish two or three years down the line like the British system.
A rare contrary voice, Mr Dermot Healy, Cork, praised the executive for its "brave if maybe stupid decision" to take part in the pilot project. He read from the Education Act detailing the new powers of the inspectorate. "This is the law of the land right now, and here we are totally rejecting it."
The general secretary, Mr Jim Dorney, also stressed that the Education Act gave the State the authority to implement school inspection and evaluation procedures "one way or the other".
He said a second reason the executive had decided to take part in the pilot project despite last year's congress decision was that the pilot would end and if the TUI did not participate it would have no opportunity to test the ideas coming out of it. People who had taken part had reported a "very positive experience".
A third reason was that there would be a conference at the end of the pilot phase and the union could not take part without some knowledge of what WSE was trying to do. He asked delegates if they wanted to let the ASTI determine policy in this area.
The vice-president, Mr John MacGabhann promised that, ultimately, TUI participation in WSE would be decided by congress, a special congress or a national ballot.