A missing photograph of a prisoner, which should have been marked “GB2”, has dominated evidence in Ben Roberts-Smith’s defamation trial on Thursday, with allegations before the federal court that “GB2” was a terrified captive teenage boy shot in the head by Roberts-Smith.

A retired SAS comrade, anonymised before the court as Person 11, has been called by Roberts-Smith to give evidence in his defamation action against three Australian newspapers, whom he says defamed him in a series of reports that alleged he committed war crimes, including murder.

The newspapers are pleading a defence of truth. Roberts-Smith denies any wrongdoing.

On his third day in the witness box, the questioning of Person 11, a close friend of Roberts-Smith’s, focused on a November 2012 SAS mission to Fasil, in Afghanistan’s southern Uruzgan province.

Under cross-examination, Person 11 was shown photographs of three prisoners, allegedly taken from a Toyota Hilux ute interdicted by Australian troops on a road through the village. The prisoners – known as Pucs for “person under control” – have tape on the back of their clothing giving details on where they were arrested including VEH for “vehicle”, RD for “road”, and, on one man’s tape, “driver”.

The three men are marked with the callsign of the soldiers who detained them – Gothic Bravo. The men are marked GB1, GB3, GB4. Their photographs – front and back – were taken at the Australian base at Tarin Kowt.

Person 11 told the court he did not recognise the men in the pictures.

Nicholas Owens SC, acting for the newspapers, told the court there was “no picture of GB2 in existence”, because the second prisoner detained from the Hilux never made it to the Australian base.

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Owens showed Person 11 a photograph of a young Afghan man who had been shot dead, his body lying next to an AK47.

Person 11 said he had never seen the young man alive, nor did he recognise the photograph of his body.

Owens put it to Person 11 that the young man was GB2, and that he had been pulled from the car by Australian soldiers, detained, and handed over to Person 11 and Roberts-Smith during the raid on Fasil.

“Mr Owens I don’t recognise these individuals nor do I recall having Pucs handed over to me,” Person 11 replied.

Owens alleged the young man was taken into a compound by Roberts-Smith, who then shot the man with his pistol.

“I reject that, Mr Owens.”

Owens said: “I want to put it to you that the reason there is no photograph of the second Puc from Gothic Bravo is that he was murdered by Mr Roberts-Smith in the compound.”

Person 11: “I disagree with that.”

Owens said the AK47 next to the young man’s body was a “throw-down”: a piece of compromising equipment placed on or near the body of a deceased person as a post-facto justification for an illegitimate killing.

Person 11 denied Australian troops ever engaged in the practice of using throw-downs.

Roberts-Smith has consistently denied the allegation he murdered a young prisoner at Fasil. Giving evidence last year, he told the court the account was “baseless”, and the event could not have happened because he never fired his pistol in combat in Afghanistan.

I never had to engage with my pistol,” he said.

Roberts-Smith also rejected assertions he used “throw-downs”. He maintained all of his actions in Afghanistan abided with the Australian troops’ rules of engagement, and the Geneva conventions.

Another Australian soldier on the Fasil mission has earlier given evidence in the newspapers defence that Roberts-Smith told him he had murdered the young man.

Anonymised as Person 16, the soldier said he had arrested two of the four men inside the vehicle, including the young man.

“I made him out to be late teens … not a fully beard, a bit chubby, and shaking in terror.”

Person 16 told the court he handed the two prisoners over to Roberts-Smith, and about 15 minutes later, Roberts-Smith said over the troops’ radio network “two EKIA”. EKIA is an initialism for “enemy killed in action”.

In the days after the mission, Person 16 said he saw Roberts-Smith at the SAS’s Camp Russell within Australia’s Tarin Kowt base, and asked him: “What happened to that young fella who was shaking like a leaf?”

Roberts-Smith allegedly replied: “I shot that cunt in the head. Person 15 told me not to kill anyone on the last job. So I pulled out my 9mm, shot the cunt in the side of the head, blew his brains out. It was the most beautiful thing I’ve ever seen.”

Roberts-Smith told the court the account was untrue and that the conversation never happened.

In his opening address to the court last year, Roberts-Smith’s barrister, Bruce McClintock SC, described the Fasil allegation against Roberts-Smith as “beyond ridiculous” and “insane”. “It’s Colonel Kilgore on ice,” he said, referencing the Vietnam war film Apocalypse Now.

“While the three fighting-age males were arrested and taken to Tarin Kowt, the adolescent boy was released,” McClintock told the court.

Person 11 has concluded his evidence. The trial, before Justice Anthony Besanko, continues.

Source: The Guardian