Winston Peters says New Zealand First isn't bound by a "unanimous" vote taken by a parliamentary committee not to release the report on the behaviour of former auditor-general Martin Matthews.
Speaker David Carter said on Friday the report by Sir Martin Wevers on the way Mr Matthews handled the Joanne Harrison fraud case when he was head of the Ministry of Transport was going to stay secret.
Mr Matthews resigned on Thursday just hours before the report was expected to be released.
Mr Carter says the Officers of Parliament committee, which he chairs and which was given the report, had voted unanimously not to release it.
Five parties are represented on the committee.
Mr Peters says Mr Carter has misrepresented NZ First's position.
"Deputy leader Ron Mark supported the decision at first but when he had a chance to consult his colleagues he told the committee he wanted to change the vote," Mr Peters said.
"The Speaker did not acknowledge that in his public statement."