Federal government MP Andrew Hastie has defended speaking to journalists about Ben Roberts-Smith, telling a court he wanted to shed light on alleged war crimes.

The former Special Air Service Regiment captain gave evidence on Monday about speaking to the media while an inquiry into war crime allegations in Afghanistan was underway.

The assistant minister for defence was accused by barrister Arthur Moses SC, on behalf of Mr Roberts-Smith, for not having courage to put his name to those allegations.

Mr Hastie said the accusations were put by numerous special forces members and he was providing support appearing in an interview on the Nine Network’s 60 Minutes program.

“The reason these allegations have come to light is because the systems have failed thus far,” he told the Federal Court.

He said the “fourth estate” was doing important work shedding light on incidents that helps “keeps democracy healthy”.

Mr Roberts-Smith, 43, is suing The Age, The Sydney Morning Herald and The Canberra Times over reports claiming he committed war crimes and murders in Afghanistan between 2006 and 2012.

The Victoria Cross recipient denies all the claims against him, while the media outlets are defending them as true.

Mr Hastie said Mr Roberts-Smith’s recollection of a 2012 mission to Syahchow both soldiers took part in painted an “alternate universe” to the one the minister had experienced.

During the de-brief with their officer in command, Mr Hastie said he was “naive” listening to his colleague provide a “different summary” of events that made little sense to him.

News outlets allege Mr Roberts-Smith ordered a young trooper to execute a prisoner during that mission.

Mr Hastie said he was made aware weeks later but that it was a “big step to accuse someone of unlawful conduct”.

“I had a gut feeling something wasn’t right.”

“I remember saying things didn’t add up on that job,” and that “the numbers” weren’t stacking up, he said.

Mr Roberts-Smith’s lawyers have repeatedly suggested allegations against the war hero were made up by a small group of peers who were jealous of his military accolades.

Mr Hastie previously listed to the court 20 people who had suggested to him that Mr Roberts-Smith was a hypocrite – that “the outward facing picture of Mr Robert-Smith was at odds with his battlefield conduct”.

He initially highly regarded Mr Roberts-Smith, but no longer was proud of him, he said, while denying that he disliked him.

“I pity him,” he said on Friday.

“I don’t want to be here… this is terrible for our country. It’s terrible for the SAS. It’s terrible for the army.”

Mr Hastie denied he had been critical of Mr Roberts-Smith to raise his own profile as a parliamentarian or that he had come to court to support the newspaper’s claims because they were giving him financial assistance in another legal matter.

The trial continues.

– AAP