The Chief Ombudsman has confirmed the Prime Minister Jacinda Ardern does not have to publicly release a 33-page coalition document.
In his final decision released this morning, Peter Boshier, ruled the document was clearly held by Ms Ardern in her capacity as Labour Party leader.
This meant it was not able to be requested for release under the Official Information Act.
He said as part of his investigation, he sought an explanation from the Prime Minister's office about the formation and use of the document, and met with her officials about the decision to withhold the information.
He also consulted the Deputy Prime Minister Winston Peters' office.
Mr Boshier said the document was created during the negotiations between the Labour Party and New Zealand First leading up to their coalition agreement and the formation of the government.
"It is quite clear that at this time, Ms Ardern held the information in her capacity as Labour Party leader.
"Although it was considered during the coalition negotiations, this document did not form part of the final coalition agreement."
Mr Boshier also asked the Prime Minister's Office whether the document had been in use since the formation of the new government, and its contents shared with any Ministers, government departments, or anyone else subject to the OIA.
He was advised that was not the case.
"After carefully considering those comments and the nature and purpose of the document, I accept that the document is still held solely in Ms Ardern's capacity as Labour Party Leader."
The National Party has demanded the release of the coalition agreement it calls a 'secret document' on a number of occasions.