The author of a book accusing the Defence Force of covering up civilian deaths during an SAS mission in Afghanistan has urged an inquiry to publicly release information.
The Operation Burnham inquiry held a preliminary hearing today to discuss how it handles classified material.
The inquiry was launched by the government after the book Hit & Run by investigative journalists Nicky Hager and Jon Stephenson alleged six civilians were killed and 15 injured in a raid by New Zealand's elite soldiers on two Afghan villages in 2010.
Mr Hager told the hearing the official New Zealand Defence Force narrative of what happened in Baghlan province left out many details, including the death of a child and other civilians.
Mr Hager said the Defence Force should not be able to pick and choose which information about Operation Burnham to share publicly or restrict.
He said the inquiry did not arise from the Defence Force scrutinising its actions and fronting up with concerns.
"The New Zealand Defence Force had years to do the right thing about Operation Burnham, but it was us, the authors, and counsel for the villagers who have raised this - but not as an attack on the defence force," Mr Hager said.
The people who lived in the Afghan villages in question wanted a largely open process with public hearings and cross-examinations, like a court hearing.
The lawyer assisting the inquiry, Kristy McDonald QC, said it was the most complex ever held in New Zealand.
Ms McDonald said the submissions received showed government agencies involved were worried the process could compromise New Zealand's security and international relations if classified information was made publicly available, and wanted a largely closed process.
The inquiry needed to proceed with great care, because of a significant risk of consequences for individuals and of public harm, Ms McDonald said.
While an open inquiry was desirable, it would not be possible in all circumstances, such as when it was found classified information could not be made public.
Some witnesses, such as Afghan nationals, whistle-blowers and defence personnel needed to be kept confidential or anonymous, she said.
The public would lose confidence in the inquiry if processes were not in place to protect national security and international relations through keeping certain information secret, Ms McDonald said.
"A do no harm approach should govern the inquiry's process," she said.
However, Mr Hager said the claims the evidence was all extremely sensitive were false.
He said security people genuinely believed the concerns they raised.
"It's the nature of their training and their peer group - security always seems the most important," Mr Hager said.
"It's not realistic to expect them to think the public's right to know, or the international law, or accountability might be more important than security."
"It's important their priorities, are not the inquiry's priorities."
The Defence Force and the Crown were short sighted in urging for openness to be minimised and for some parties to be excluded, Mr Hager said.
Davey Salmon, the lawyer for co-author Jon Stephenson, agreed the inquiry needed to be open, so "the sunshine could be shone on this".
While the inquiry had to carried out with an open mind to ensure public confidence in the process, the allegation of a cover up had to be looked into, Mr Stephenson said.
It would be "dangerous" for NZDF personnel to decide which documents were relevant and which ones were classified.
That was a natural justice issue that needed to be brought to the panel's attention, he said.
Sir Terence Arnold opened the hearing and said the processes the inquiry adopted must give it the best opportunity to uncover the truth.
The hearing is set down for two days.
Lawyers for the former residents of the Afghan villages, for Mr Stephenson, the Crown, the Defence Force, and the media will have their say. Mr Hager is representing himself.