As the former head of New Zealand's military this week rejected allegations of a cover-up, a major question loomed: How did a file showing the Defence Force had been wrong in saying no civilians could have died during a SAS-led raid in Afghanistan end up locked away in an NZDF safe for years?
A Government probe is looking into Operation Burnham, after the 2017 book Hit & Run alleged six civilians were killed and 15 others wounded during the counter-insurgency raid in August 2010.
Until 2014, the Defence Force said allegations of villagers being killed were "unfounded". Afterwards, they were possible. Officials also briefly went back to rejecting the claims after the book came out, before correcting the record again.
This week, former chiefs and other top brass were asked to explain why the story changed.
Here's what we learnt:
How the military got it wrong
The short explanation, according to the Defence Force, is one misunderstanding.
After Operation Burnham, the International Security Assistance Force (ISAF) – the coalition forces in Afghanistan – investigated whether civilians may have been killed. It eventually cleared New Zealand's troops, who were on the ground, but found a gun-sight malfunction on a US Army helicopter providing air support led to rounds accidentally hitting two buildings, possibly killing villagers.
ISAF raised the issue in a press release a week after the operation and even showed video footage to a New Zealand officer who told the inquiry he also felt civilian casualties were possible.
Enter Brigadier Chris Parsons, who on his first full day as the top SAS officer in Afghanistan went to ISAF's command centre, and came back saying, incorrectly, civilian deaths had been categorically ruled out.
Parsons told the probe an American officer – who he could not identify – had only let him see one, four-line paragraph of the ISAF report, which had not been cleared to be handed to New Zealand.
Parsons explained he had misunderstood an acronym, which in addition to a chat with the American, led him to reach an erroneous conclusion about the findings.
"He turned to the final page of the document and, pointing to the first paragraph of that page told me that was what I needed to know," Parsons said.
He told the inquiry he had read "AF" as "air force", thinking it referred to the US Army helicopters, when in fact it cleared the "assault force" on the ground.
Parsons emailed his bosses that night with the news.
After that, the inquiry heard, the matter was settled for the Defence Force's commanders back home. Parsons' account became the official line and was passed onto Government ministers and the public for years to come.
Retired Major General Peter Kelly (then the Director of Special Operations) told the probe Parsons was highly trusted, and even though it was soon after made clear he had only seen a fragment of the report, the earlier information was set aside. Parsons' account was the only direct link to the final report, Kelly said.
How the story changed
When questions came up again in 2014, then Defence Minister Jonathan Coleman asked for a briefing. A bundle of files was taken from a safe inside NZDF headquarters and given to him.
It turned out the Defence Force's copy of the ISAF report had been in there since September 2011 – but had never been made public.
Even more curiously, though, it had been marked and annotated by someone - showing it had been read.
An incensed Coleman called then Defence Force chief Tim Keating asking how a report contradicting what he had been told had been locked away for three years. The minister the next day publicly said he could not rule out civilian deaths.
When Hit & Run was released in March 2017, the military again called the allegations unfounded.
The NZDF's lawyers described that as a "regrettable" accident this week, saying with a lack of time to respond and amid confusion, staff had reached for an outdated press release.
So the questions became: who had locked the file away and why had they not told anyone about it?
And there seemed to be few answers.
Keating told the inquiry he was shocked to learn the NZDF had the report.
The man who put in the safe – Deputy Chief of Staff Michael Thompson – said he had never read it and couldn't remember who gave it to him, although under questing narrowed it to about 15 people. His personal register provided no clues.
And the man who in 2014 was tasked with investigating how the file reached the safe - retired commodore Ross Smith – told the inquest he never managed to find out.
It seemed a cold trail until the inquiry's chair, Sir Terrence Arnold, on Thursday morning surprised the room by raising the possibility of a second file register and quickly ordering for a copy to be fetched.
The question was prompted by a marking on a file that appeared to allude to an alternative log system - one the inquiry did not know existed, having only been alerted about the file in the safe a week prior to the hearing.
It took staff about 15 minutes to hunt the document down - and it showed the ISAF report had been signed in by the office of the Direction of Special Operations, Jim Blackwell, on September 1, 2011.
Blackwell wasn't on the list of witnesses, leaving Keating to explain the former director had a "high level of integrity I would not question".
Amid questioning about whether the file had been "buried", Keating would only concede to sloppy record-keeping.
"It wasn't tidy, it was unprofessional, but it wasn't a conspiracy," he said.
So what happens now?
The last-minute evidence prompted the inquiry to be suspended to call new witnesses and recall a number involved in the handling of the ISAF report.
That may include bringing Blackwell in. He left the Defence Force in 2015.
When the hearing will resume has not yet been confirmed.