In their new book, Hit & Run, Nicky Hager and Jon Stephenson have used various sources, including military insiders, to suggest that there was participation by New Zealand forces in unnecessary civilian deaths in Afghanistan, and in improper targeted killings of apparent insurgent forces and the handing over of another insurgent to be tortured by Afghan forces.
They also set out a view that there was knowing misrepresentation of what had happened.
Some people will no doubt respond by pointing to truisms that war is a dirty business and "collateral damage" is an unavoidable consequence of operations that are necessary to ensure that there is a wider safety in the world.
But the ethos of operations by New Zealand forces is based on the more palatable view that the business of war should be carried out cleanly.
This means that where things appear to have gone wrong, there should be transparent inquiries through which lessons can be learned, wrongdoers brought to account, and victims and their families compensated.
Hager and Stephenson's account gives grounds to suggest that something did go wrong. The chronology they say is established from their investigations can be summarised briefly.
The response to the death of Lieutenant Tim O'Donnell on August 3, 2010 was the planning of an operation to kill the leaders of a new group of insurgents believed to be responsible. This was a New Zealand SAS operation supported by US air power.
It is portrayed by them as a revenge attack: however, there is no doubt an alternative account, namely that those who had targeted Lieutenant O'Donnell's patrol would continue with those activities, such that an operation against them was legitimate pre-emptive self-defence.
But when Operation Burnham was carried out on August 22, 2010, the insurgents were not present in the two villages at its centre: intelligence to the contrary was wrong.
Instead, six civilians, including a 3-year-old girl, were killed through the destructive power of an American Apache helicopter and possibly sniper bullets that felled some "squirters" seeking to run away from the scene of the assault.
Press releases issued, including from the New Zealand Defence Force, have denied civilian deaths and portrayed this as an operation that successfully led to the deaths of insurgent forces.
The insurgents had links with the villages but were away in the mountains at the time of the raid, though they returned for the mourning. Before the operation, they had been placed at the request of New Zealand forces on the Joint Prioritized Effects List, the Orwellian title for a capture or kill list.
Subsequently, most were killed in 2011 and 2012 (along with people around them). One, Qari Miraj, was located in a mosque in Kabul in 2011, which presumably saved his life.
But New Zealand forces handed him over to the Afghani National Directorate of Security, which was suspected to be a place of torture: UK forces were not allowed to take people there for that reason.
He was indeed tortured, tried and imprisoned but a brother replaced him in the insurgency and he was later to escape from prison and renew his activities.
There are some political points in Hager and Nicholson's account. Limited references to politicians in the narrative will no doubt get disproportionate headline coverage.
They also question whether the SAS has a disproportionate influence in the Defence Force.
Points are also made about the inadequacy of any rationale for New Zealand forces to be present in Afghanistan beyond wanting to be in the club with the USA. But the main concern is for there to be a proper investigation to lead to any necessary accountability.
They are on solid ground with this call. Although the Defence Force has reiterated the position that there were no civilian deaths in the raid of August 22, 2010, the conflicting account in Hit & Run cannot be lightly dismissed.
It seems to have solid research behind it. This means that we have conflicting accounts in relation to the important question of what happened.
Establishing the truth is important as a matter of law. One legal lens for this is international criminal law and its demand for investigations into possible war crimes. Another lens is that of human rights law, which is not suspended when there is an armed conflict.
The propositions from human rights law are that arbitrary - that is, unjustified - deaths are a breach of the right to life and that participation in events that lead to torture can never be justified.
Importantly, assessing whether a death is arbitrary involves determining not just whether service personnel were justified in reacting as they did when confronted with a fast-moving situation, but also whether the operation was planned in such a way as to minimise the risk of avoidable death. In short, negligent planning and implementation can breach the right to life.
Since the facts are important, there is an additional proposition that establishing solid evidence that the state might have breached its human rights obligations requires an effective and independent investigation.
The question arising now that Hit & Run is out is whether it demands an independent investigation: the answer is surely that it does.
This coincides with what is sensible from a political perspective. If the Defence Force is correct, its position needs to be vindicated.
If those who have given information to Hager and Richardson are accurate, whether wholly or in part, lessons need to be learned and accountability established.