Investigative journalist Nicky Hager has told an inquiry the military breached the Rules of Engagement (ROE) in Afghanistan.
The Operation Burnham inquiry is investigating allegations in the book, Hit and Run, that six civilians were killed in Afghanistan during a New Zealand-led raid in 2010, and the military covered up what happened.
A public hearing was held in Wellington today.
Hit and Run's co-author, Nicky Hager, directed the inquiry to an order from a United States commander, General David Petraeus, who at the time said: "The commander approving the strike must determine that no civilians are present."
Hager told the hearing: "Currently four out of five attacks conducted during Operation (Burnham) strongly appear not to be compliant with the Rules of Engagement and [General] Petraeus' civilian protection directive."
He said former prime minister John Key along with two former chiefs of defence and some SAS officers needed to be held to account.
"I believe it is essential that NZDF as an organisation is held publicly accountable for the civilian causalities, the lack of care and aid afterwards and the cover-up of Operation Burnham," he said.
However, earlier in the public hearing, former Defence minister Wayne Mapp - who held the portfolio at the time in 2010 - said he was satisfied the SAS met the obligations of the Rules of Engagement.
Dr Mapp said he was being kept regularly updated and made sure the ROE met both domestic law and the law of armed conflict.
He said he was also being kept informed of reports of detainee mistreatment by Afghan authorities - but was assured by officials that New Zealand's SAS had no part to play.
"It is important to understand that our mission in Afghanistan was to help build the capability of Afghan forces to govern and manage their society in accordance with international law.
"We were there to assist and not to impose," he said.
Further public hearings for Operation Burnham are expected in July.