Our military's Operation Respect programme to eliminate harmful and inappropriate sexual behaviour is destined to fail without fundamental change, an oversight report has found.

The independent report from the Ministry of Defence is a damning dissection of the NZ Defence Force's culture-changing project, launched in 2016 to stamp out sexual abuse, assaults and harassment.

It has found the "lack of transparency and accountability" in NZDF's progress in addressing sexual violence harassment and discrimination.

The report also identified a "code of silence" that stopped people raising concerns because "they fear the repercussions and do not trust NZ Defence Force processes and systems".

There were also problems with the culture of military discipline and command that made it difficult to speak out against behaviour or decisions made by those higher in the hierarchy.

"A strong and repeated view is that there is nowhere to go."

In an astonishing recommendation, the Ministry of Defence review said measuring the success of Operation Respect should no longer be left solely to NZDF.

Instead, it has recommended the Auditor-General carry out a review of NZDF progress every two years for the next 20 years. The Herald has been told the Chief of Defence Air Marshal Kevin Short has already had discussions with Auditor-General John Ryan.

It also urged NZDF to make available an external means for people to raise complaints, recommending it meet with the Chief Ombudsman to find a way for its personnel to raise issues outside the military.

The report, written by Debbie Teale and Dr Carol MacDonald after research and interviews with more than 400 military personnel, found sexual abuse and assault - from bullying and harassment through to physical sexual violence - continued to have "serious impacts" on the wellbeing of NZDF's 12,000 personnel.

"We also heard how the NZDF's failure to act or resolve situations in a timely way often compounded the original trauma and resulted in highly stressful situations for all of those concerned, including wider personnel and staff."

The Ministry of Defence review commended NZDF for setting up Operation Respect, saying the establishment of Sexual Assault Response Teams and sexual ethics training across the entire organisation provided a good foundation for generational change.

But it said "there has been insufficient progress since the plan was launched".

It had failed to win over staff, with many spoken to saying "they believe the approach is reactive or tick-box, more about making the NZDF 'look good' rather than changing the culture".

It found there were examples of Operation Respect being used in "a joking, if not derogatory manner". The Herald has had service personnel refer to it as "Operation Don't Rape Anyone".

The report found the majority of the work done appeared to be focused on responding to complaints and supporting those who had raised incidents or issues, with little done to build a prevention culture.

Of those prevention steps taken, it said they appeared to be "light-touch" and "untested" and "do not appear to be part of a deliberate strategy".

In terms of managing Operation Respect, the report found leadership lines were confused, funding was insufficient and the roles and responsibilities of those involved were unclear.

NZDF's specialist sexual abuse response team was over-stretched, had a high turnover and there was a "real risk of the entire team leaving the NZDF".

The Herald was given the Ministry of Defence review by the NZ Defence Force ahead of its public release, along with a briefing by Chief of Air Force, Air Vice Marshall Andrew Clark, the services' champion of Operation Respect.

Doing so allowed Clark to offer NZDF's response to the bleak and blunt statements about Operation Respect at the same time as the report was released.

Clark said there was an awareness inside NZDF that Operation Respect was failing to deliver on promises made in some regards.

However, he said the Ministry of Defence review showed greater problems than had been anticipated.

He said it highlighted the need for NZDF to maintain a constant effort to make Operation Respect sustainable. In contrast, the report showed it had been "losing momentum and losing focus".

He said he welcomed the review every two years. "I would be delighted to have something that keeps pulling us back and keeps a focus on the cultural change journey."

Clark said it was now recognised greater effort was needed to permeate the change required by Operation Respect throughout NZDF.

There was also a need to shift the perception from Operation Respect being "the voice out of Wellington" and to find ways to engage different parts of the organisation. "This can't be 'one size fits all'.

Clark said the part of the report that had the greatest personal impact on him was the term "Code of Silence".

In an interview in February, Clark told the Herald that he was personally available to take complaints from those who had suffered abuse and assault and had done so - even leaving his Wellington desk to fly and meet with complainants.

"I had hoped we had made better progress."

One of the trigger factors for the establishment of Operation Respect was the conviction of Royal NZ Air Force Sergeant Robert Roper, who was sent to prison for 13 years on 20 counts of raping and sexually assaulting his daughters and others.

An inquiry into Roper's service found a permissive culture allowed him to carry out a tyranny of abuse and assault against his children and others - including Air Force colleagues.

Tracey Thompson, one of Roper's daughters, said it had been expected it would take a generation for change to take hold in NZDF.

"They had to get everyone in charge on board. They had to come around to the fact this was happening."

She said she had faith in Clark as NZDF's champion of Operation Respect. "They have got to be allowed to have time to change."