A former elite soldier has told a court that weak leadership within Australia's special forces let down Ben Roberts-Smith and his patrol members after accusations of war crimes surfaced.
Mr Roberts-Smith, 43, is suing The Age, The Sydney Morning Herald and The Canberra Times for defamation over reports claiming he committed war crimes and murders in Afghanistan between 2006 and 2012.
He denies all the allegations that the news outlets are defending as true.
The witness codenamed Person 31 told the Federal Court on Monday he was concerned by allegations coming from the Victoria Cross recipient's own patrol members.
The former SAS commander was told one of Mr Roberts-Smith's squadmates had watched the decorated soldier kick an unarmed Afghan prisoner off a cliff in Darwan in 2012, he said.
More things "came to light" as he neared his departure from the force in 2014.
And he felt Mr Roberts-Smith and his team were failed by the system and the lack of a prompt inquiry - not allowing the men to move on.
Due to "weak leadership" the allegations were not investigated by the command, he said.
"And hence we're now dealing with this in court where nobody wants to be," Person 31 said.
Person 31 said he observed Mr Roberts-Smith during a pre-deployment training exercise near Perth with two young soldiers dubbed Person Nine and Person 10 in a makeshift compound.
Later he heard another soldier anonymised as Person Seven say words to the effect of "Oh for f*** sake", referring to Mr Roberts-Smith orchestrating a mock execution where one soldier pretended to shoot a fake prisoner.
"I would have been disappointed. I would have said something along the lines of for f*** sake did that really happen," he said.
Person Seven earlier testified that he watched the former SAS corporal order a subordinate to "f***en kill" the fake detainee, while the soldier looked confused.
That soldier - Person 10 - told the court last week that Mr Roberts-Smith ordered him to "shoot" and he eventually went "bang bang".
"Are you good with that, because that's how it's going to be when we're over there," Mr Roberts-Smith allegedly told the trooper.
Person 31 on Monday said following the alleged training incident he walked past Mr Roberts-Smith outside their accommodation and stopped for a quick chat.
"Pull your head in, you can't be doing s*** like that," Person 31 said he told him.
"I recall him looking down, grunting, nodding and walking off."
Under cross-examination, Person 31 admitted he had not seen any of the alleged war crimes, but that he trusted the comrades who had told him.
It follows the evidence of Person 10, who said the war hero punched him in the face after mistakenly firing in the direction of two civilians.
Person 31 said he recalled Mr Roberts-Smith was notably angry during a meeting that followed the incident, and Person 10 was subsequently moved into his patrol in a "fragile state".
He said the soldier under Mr Roberts-Smith's guidance had not been adequately mentored, but eventually let himself down before his dismissal.
The trial continues.
