The High Court has found the man who blew the whistle on possible financial impropriety at the Te Kōhanga Reo National Trust acted with integrity and in accordance with his duty as a trustee.

Toni Waho was removed from the trust's board by fellow trustees in November 2014, High Court Judge Karen Clark said. He is a former director of the Atihau Whanganui Incorporation and former principal of Te Kura Kaupapa Māori o Mana Tamariki in Palmerston North.

He had been a trustee of the national Te Kōhanga Reo body for eight years when he went to the minister and associate minister of education behind the board's back to tell them of allegations of financial impropriety in the board and its financial arm, Te Pātaka Ōhanga. His fellow trustees said that had brought the trust into disrepute, and removed him from office.

That had a huge impact on Waho's life and health. His case was heard in the High Court last year.

He went to the court to get a determination on whether he had brought the trust into disrepute, and whether his removal from the board was lawful.

Judge Clark issued her decision on July 31. She said Waho acted with a sense of personal integrity and it was his duty to tell ministers about the allegations and take steps to address them.

He had not brought the trust into disrepute.

"Arguably it was the board and trustees who were brought into disrepute," the judgment said.

Therefore Waho was unlawfully removed from office, and is entitled to the $29,000 honorarium he would have received between 2014 and the judgment if he had still been on the board.

Waho is believed to be in Australia at present, and Atihau Whanganui Incorporation chairwoman Mavis Mullins said the rift with the trust had affected him severely.

In a media statement, Waho said he was extremely saddened that his fellow trustees thought he had brought the trust into disrepute, and was overjoyed by the judgment in his favour.

He was very happy to have "won the protection" he sought through court action.

He said he had only ever done what he thought was in the best interest of the Kōhanga movement.

"My daughter enrolled in Te Kōhanga Reo o Te Āwhina in Palmerston North when she was 1. For the following 30 years, my family and I devoted ourselves to upholding the philosophy of Te Kōhanga Reo. My disclosure of the existence of allegations to the ministers of education was to protect Te Kōhanga Reo."

The board's trustees were replaced by new trustees elected by Kōhanga whānau last year.

"I wish the new trustees of the national board the very best, as well as the whole movement," Waho said.