A gatecrashing by ACC Minister Nick Smith yesterday quickly turned an otherwise routine meeting into another scene in the ongoing political imbroglio over the scheme.

Dr Smith turned up unannounced at a select committee hearing on ACC and then talked over its chief executive, leading to accusations of "bizarre behaviour", "bullying" and "gagging" from Labour.

The transport and industrial relations select committee was meeting for ACC's financial review and was to be addressed by its chief executive, Jan White, and new chairman John Judge, appointed only on Monday after Dr Smith sacked Ross Wilson.

Mr Judge could not make the meeting but instead of being replaced by another of the board's members, Dr Smith decided to stand in, even though he was not minister during the 2007-08 year in question.

Dr Smith has already been accused of gagging the board, but he went further at yesterday's meeting by interrupting Dr White as Labour MPs tried to question her about ACC's financial position.

Its financial position is contentious. Dr Smith's National Government says cost blow-outs mean cuts are required.

Labour says Dr Smith is manufacturing a crisis in order to bring about the changes.

He stood in on the committee so he could continue to "spin" his version of its financial position.

Labour's standpoint was backed yesterday by Herald economics editor Brian Fallow, who said National's "shrill scaremongering" was irresponsible, and actuary Jonathan Eriksen, who called it complete nonsense.

Dr Smith's arrival meant the committee started 45 minutes late, after arguments behind closed doors and advice from the Clerk of the House about whether he could speak.

After only a short time, the media and public were again asked to leave as further arguments ensued.

Once resumed, the meeting continued to break down frequently as Dr Smith took over questions asked of Dr White.

Labour's attempted questioning of Dr White included whether ACC was insolvent, following Dr Smith's public descriptions of it being "technically insolvent". Labour's questioning also established that the main driver of ACC's financial position was the global economic crisis rather than the increasing costs of claims.

Dr Smith frequently interrupted and stated his opinion.

Labour MP and former ACC Minister Maryan Street, who sat on the committee, said:

"By limiting and intimidating the chief executive he is able to spin his line that we all know is a subterfuge so he can dismantle ACC and scrap what people get now."

Ms Street said the board members, even if they were about to be sacked, as Mr Wilson was, were accountable for the financial year in question and could have attended the meeting in the chairman's absence.

Labour leader Phil Goff said Dr Smith's behaviour was bizarre and called into question whether he was fit to continue as minister.

Dr Smith rejected the allegations of bullying and gagging as being "overcooked".

He said he was invited to the committee by its chairman, National MP David Bennett, when he informed him that Mr Judge could not make it.

Dr Smith said the deputy chairman or another board member were not invited because the board was about to change.

He agreed the committee was a "circus" but blamed the Labour MPs rather than himself, saying, "I was trying to help."