An investigation into allegations of "fight clubs" at Mt Eden Corrections Facility was fair and the resulting report without error, a High Court judge has found.

Serco had sought the judicial review into the investigation by the chief inspector of prisons, which was carried out after reports of organised fights and contraband surfaced on social media.

The Department of Corrections invoked a "stepping in" clause in Serco's contract in July last year and in December confirmed the British-based company's contract would not be renewed at a break point in March.

Serco launched legal action, claiming the investigation had departed from the terms of reference, contained errors of law, and had omitted relevant factors.


Tonight, Corrections chief executive Ray Smith announced that it had received the High Court's judgment in relation to the judicial review.

"In her summary the judge notes that, 'The investigation was fair and the report is without error," Smith said.

"There is now a period in which the parties have the opportunity to consider the judgment and as such I do not intend to make any public comment on this in the interim.

"I must consider when and in what form the [chief inspector's] report is to be released to ensure any security and privacy issues are managed which is why I will be consulting with the Office of the Ombudsman."

Serco was seeking an order that before the chief inspector's report was released, it was revised to "provide a fair and accurate account of the situation at Mt Eden".

Serco Chief Executive Mark Irwin said the company noted the decision and accepted it.

"We have always accepted the recommendations of the report, but brought the proceeding because we had genuine concerns about the process.

"We have acknowledged that under our management, following a period of good performance, standards in Mt Eden slipped in early 2015, and we have apologised for this."

Serco was supporting Corrections' management of Mt Eden by providing staff and other transition resources, Irwin said.

It continues to manage the Wiri Prison in South Auckland and that had been operating well, he said.

"All prisons have to deal with challenges, and we are grateful for the partnership of the Department as we work together to address them."

Serco had been in charge of Mt Eden prison since 2011, having won a $300 million, 10-year contract.

In April, the Government announced it has charged Serco $8 million to cover the costs of resuming control of the prison.