Government MPs have cleared the Environmental Protection Authority's chief executive of misleading a select committee earlier this year, leaving the National Party incensed.
MPs questioned whether Allan Freeth had misled them in February when he said he had not discussed the EPA's independence or views with the associate environment Minister.
RNZ later revealed Eugenie Sage had forwarded a highly critical media article about the EPA's outspoken chief scientist, Jacqueline Rowarth to Dr Freeth.
Ms Sage also said they had met and discussed Dr Rowarth's controversial comments on irrigation.
Dr Rowarth resigned in February.
In April, Dr Freeth reappeared before the committee, saying Ms Sage had subsequently acknowledged she had been mistaken about the meeting and he also defended her sending the critical article.
The government MPs on the select committee were satisfied they were not misled, but the National Party said Dr Freeth's original answers in February were "misleading at best, dishonest at worst".
"Any reasonable person would have concluded from the EPA's answers that no issues had been raised about the chief scientist when the issue had been raised at the highest levels involving the ministry's chief executive, both Minister Parker and Minister Sage and the prime minister's chief science advisor," the National MPs wrote in their minority report.
The independence of the EPA had been compromised, they wrote.
The EPA issued a statement saying it was pleased Dr Freeth had been cleared.
"The Environmental Protection Authority will be making no further statements or accepting any requests for interviews on the issue," it read.
Eugenie Sage also issued a statement saying she rejected National's "unfounded allegations" that she interfered in any way in Dr Rowarth's employment or acted inappropriately.