The prospect of multiple prosecutions of members of the Australian Defence Forces over alleged war crimes in Afghanistan appears dim.

The passage of time, the manner in which investigations have been conducted to date and the alleged departure of many personnel to countries beyond Australia's extradition powers are all factors that make prosecution difficult.

The story of how the investigation and pursuit of alleged war crimes has unfolded has also raised questions about the way Australia's military justice system works.

Twenty-six thousand Australians served in the long war in Afghanistan. Forty-one lost their lives in operations. Thousands continue to live with the physical and psychological scars of their service.

But the war also caused a different type of wound for the country as a whole: A challenge to our sense of always being on the side of the angels in foreign conflicts.

And of our soldiers being beyond reproach.

In September, Defence Minister Richard Marles officially closed the Brereton inquiry — an investigation into allegations of war crimes that began eight years ago — in 2016.

In a statement to federal parliament, Mr Marles said: "The allegations which are the subject of the Brereton report are arguably the most serious allegations of Australian war crimes in our history.

"The Brereton report concluded there was credible information of unlawful conduct; the most disturbing of which was the identification of 23 incidents involving 25 Australian Special Forces personnel," he said.

The Brereton inquiry's work was extensive: hundreds of interviews, thousands of hours of testimony and more than 60,000 pages of evidence.

But problems quickly emerged around how government and Defence would respond to its findings and recommendations, and about how those grim findings would turn into possible criminal prosecutions.

'Ongoing anger and bitter resentment'

The first controversy concerned the question of whether service medals would be revoked.

The then chief of the Defence Force, Angus Campbell, responded to the initial release of the Brereton report in November 2020 by announcing he had accepted a recommendation to remove the meritorious unit citation from the Special Operations Task Group (SOTG) — a move that would have affected around 3,000 SOTG personnel.

"These findings allege the most serious breaches of military conduct and professional values," he said.

"The unlawful killing of civilians and prisoners is never acceptable.

But General Campbell's decision was subsequently overturned by then defence minister, Peter Dutton.

Some issues though have remained outstanding.

Mr Marles said last month the last two recommendations of the Brereton report to be dealt with involved "me writing to relevant commanders about my decision in relation to medals awarded to them as part of their service during periods proximate to the incidents which are at the heart of the Brereton report".

"I have now written these letters."

But causing deeper bitterness in Defence ranks was the question of who should share the blame for what is alleged to have happened.

The Brereton Inquiry controversially found that responsibility for what is alleged to have happened resided overwhelmingly at the level of patrol commander.

When the current government commissioned a review — led by former intelligence chief Vivienne Thom — of how Defence was implementing Brereton's recommendations, the review panel disputed the Brereton findings on the chain of command issue, saying:

"More senior officers have to take some level of responsibility for what goes wrong in their organisation, or at least for any circumstances or policies that permitted or facilitated it.

"If no one at an appropriate level of authority knew anything about the misconduct, that is an organisational failure in itself."

The Thom Panel also documented the corrosive impact on Defence morale of the Brereton report's findings that senior commanders were not culpable for what had happened.

It found that:

"There is ongoing anger and bitter resentment amongst present and former members of the Special Forces, many of whom served with distinction in Afghanistan, that their senior officers have not publicly accepted some responsibility for policies or decisions that contributed to the misconduct (such as the overuse of Special Forces).

"The Panel considers that the failure to look closely at the collective accountability and responsibility of Defence's most senior leaders continues to generate resentment and anger amongst veterans, soldiers and their families which is likely to last for a long time."

Professor of International Law at the Australian National University Donald Rothwell says that "obviously, individual members of the armed forces are making decisions on the ground with respect to the way in which they open fire and ultimately use lethal force".

"Those are not matters that are being directed through command centres or in Australia through ADF command.

"I guess the bigger question … was what was the level of knowledge that ADF commanders had about the alleged conduct of members in the field, and that was an issue that wasn't really properly settled by the Brereton inquiry."

Just one member of the ADF has been charged over war crimes — charges that flowed from an ABC report.

'Very difficult for investigators'

The job of investigating the alleged war crimes documented in the Brereton report, with a view to prosecution, was given to a new body, the Office of Special Investigator.

But it is now investigating events eight years on from the beginning of the Brereton inquiry, and 19 years since the first alleged incident in Afghanistan, in 2005.

That's left many observers questioning the likelihood of any successful prosecutions.

None of the interviews collected by former justice Brereton, or anything derived from the interviews which exposes the compelled witness to risk, can be used in a prosecution.

As Mr Marles told federal Parliament last month:

Lawyer and defence analyst Glenn Kolomeitz explains that the Brereton report "was an internal Defence administrative inquiry, exercising coercive powers".

"In other words, witnesses are compelled to attend and give evidence. So they have to attend, they have to answer questions and give truthful evidence. But the trade-off there is that the use of the evidence, whatever evidence they've given, is immune from use against them in a criminal trial.

"It's what's called use immunity, or derivative use immunity.

"However, the immunising of the evidence of these people would almost undoubtedly have an impact on subsequent criminal investigations.

"Any lawyer, any counsel worth their salt, would be in there arguing that that evidence being used against their client was derivative of immunised evidence, so of evidence obtained under compulsion, under coercion."

Rawan Arraf, principal lawyer at the Australian Centre for International Justice, agrees that, at the international level, there are also going to be issues, particularly going to the question of the chain of command.

"There's also a broader legal, international legal question on whether or not this is consistent with international criminal law and international law," she told 7.30.

"I think that this is going to be one of those issues that will really be monitored and looked at by not just defence counsel, but keen observers of international criminal law .

"Whether or not Australia will be in compliance with its international obligations — including its Rome Statute obligations — and whether or not that might give rise to prosecutions at the International Criminal Court, if Australia is not seen as genuinely investigating its allegations of these crimes."

Professor Rothwell observed that Australia did not have an established way to investigate war crimes.

"Rather remarkably, Australia became a party to the Rome Statute of the National Criminal Court in 2002. It set up a very elaborate and appropriate set of legal requirements under the Commonwealth criminal code, but there was really no mechanism for the investigation of Australians committing war crimes," he said.

"And of course, that meant that there was no real mechanism for the investigation and the collection of evidence.

"And that's why the really significant turning point was the decision of the former government to properly establish a fully equipped body to conduct effectively a war crimes prosecution, and that's the Office of the Special Investigator."

'Justice delayed?'

There are a number of other obstacles to prosecutions.

Mr Marles admitted in parliament last month that "any prosecutions which are pursued by the Office of the Special Investigator (OSI) will take years to complete".

At Senate estimates hearings earlier this year, Greens Senator David Shoebridge quizzed the head of the OSI about the progress of investigations.

"Nineteen people have been referred to your office for criminal investigation," Senator Shoebridge said.

"Is it true that, almost two decades after that 2005 incident — the first incident that was referred to in the Brereton report — only one person has been charged?"

"We are, like the Brereton report, looking at the period of 2005 to 2016, and the DPP has charged one Australian soldier for a war crime," Chris Moraitis, OSI director-general, said before he admitted under questioning from Senator Shoebridge that "justice delayed" was "justice denied".

Mr Moraitis added: "If you're going back to 2005, and, assuming there was a crime committed in 2005, I'd say time is ticking away. We've always said we want to move as quickly as we can."

Investigators have also not been able to get into Afghanistan, which Mr Moraitis backed up when asked by Senator Shoebridge if his office was making any arrangements to speak with the families of victims there.

"No, we haven't, because it is almost impossible to engage in Afghanistan," Mr Moraitis said.

Ms Arraf said that although it remained a challenge to enter Afghanistan she would like to see more done.

"It's always a challenge not to be able to access the scene of the crime itself and the country in which the allegations took place, but at the same time, I think that we've seen journalists who have gone back to engage with the victims' communities themselves in Uruzgan, and have been able to access the country and speak with them and engage with them on various number of issues," she said.

"So it's really a broader question for the OSI in terms of where their evidence leads, and whether or not they require access to the scene of the crime in order to conduct really effective and genuine investigations.

"But to the broader issue, we would say that the government, the OSI and the [Australian Federal Police] and the prosecutors should provide greater engagement with the victims' communities."

Senator Shoebridge also put to Mr Moraitis that some of the 19 people who had been referred to the OSI "are actually in countries without an extradition treaty, engaging in mercenary activities".

"There are people we are investigating who are offshore, yes," Mr Moraitis said.

A 'broken' system

Given that the long delays to date make the outcomes of justice highly unsatisfactory for the victims, it raises the broader question of how the system of military justice actually works, and of how Australia might better deal with allegations of war crimes in the future.

Questions about Australia's military justice system have been long-standing — and have been a live issue over the course of recent wars in Iraq and Afghanistan.

What's made the current controversy more contentious is that it has dealt with war crimes investigated long after the battles have ended, which have drifted into the realm of the civil legal system.

Problems within the military justice system itself — which have nothing to do with Afghanistan — are very much still in play.

The just concluded Royal Commission into Defence and Veteran Suicide was damning of the system.

"Our inquiry has identified failings within the military justice system that have the potential to damage the wellbeing of and contribute to suicide and suicidality among serving and ex-serving members," it found.

"The consequences of poor administration of the military justice system can be devastating for individual members. It undermines trust in the integrity of the system at each of the unit, service and enterprise levels.

"Data we obtained shows that ADF members who have been involved in the military justice system are at an increased risk of suicide."

Mr Kolomeitz says change must come from inside Defence.

"We've had decades of inquiries into military justice in this country," he said.

"Every so many years an inquiry rolls out, Defence will initially deny that there's an issue, then eventually they're backed into a corner and they'll concede, and say, 'OK, we'll change.' No changes are forthcoming.

"Finally we get this royal commission, which was into Defence and veteran suicide, but at the end of the day, a lot of it came down to military justice and the way our people are treated through that process.

Professor Rothwell says that government will have to seek to establish a full-time mechanism for investigating alleged war crimes.

"The Office of the Special Investigator was a response to the Brereton inquiry. It's being tested. It's been probed at the moment. But there'll need to be a more established mechanism ongoing."

Mr Marles is currently considering both the recommendations of the royal commission and a separate review of the role of the Inspector-General of the ADF (IGADF), a body that is supposed to act as an independent umpire outside the military chain of command on matters of military justice.

A spokesperson for the minister said these were considered together "to ensure a holistic and pragmatic approach to any proposed reform".

"To respond to one report in isolation of the other would be impractical and ineffective," they said.

"The deputy prime minister has said the government will agree to implement the thrust of the recommendations of the royal commission, of which reform to the IGADF and military justice system forms a part."

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