The father of a young man who drowned after walking out of the mental health unit at Waikato Hospital unsupervised wants the government to release its inquiry into mental health.

Photo: Give a Little

Nicky Stevens, who was 21 and suffered from schizophrenia, died in Waikato River in March 2015.

The inquiry into the country's mental health system was finished this month but the government isn't releasing the documents to the public for another five weeks.

Mr Steven's father, Dave Macpherson, said many people put their time and energy into the report and deserve to see the results.

"That's a public report, it's of extremely high public interest."

"I can't see any reason for anything to be kept secret."

He said if the government wants the public to be confident that they are having a say, then it needs to trust the public to be involved in the debate.

"By keeping it for five weeks away from the public and having a vested interest group giving advice to the Minister, it all sounds like people protecting their own backsides."

He has also flagged issues with the Health Minister David Clark's choice of group to advise him of the reports recommendations.

The group is mostly made up of DHB representatives and the Ministry of Health's Mental Health Director John Crawshaw.

Mr Macpherson said many of those included will merely maintain the current system, and Mr Crawshaw has previously opposed a mental health inquiry.

"Putting those accountable for the current mess, in charge of suggesting the answers, is like putting a fox in the chicken run at night, and expecting your feathered friends to still be intact the next morning."

He isn't confident that any meaningful change can come out of the report, without wider advice and debate.

"There's a gnawing feeling that people are just going to suggest a few tweaks around the edge and we're not going to get the radical change we need.