Roberts-Smith, 42, is suing the publishers of the Sydney Morning Herald, The Age and The Canberra Times over media reports from 2018 that he says depicted him as a criminal who broke moral and legal rules of military engagement in Afghanistan.
He is also suing over reports alleging he assaulted a woman in a Canberra hotel room.
He denies all the claims against him, while the publishers advance a truth defence.
Taking the stand at the Federal Court trial in Sydney on Thursday, Roberts-Smith said claims critical of his war service by the respondents’ legal team were based on “rumour and innuendo”.
“I spent my life fighting for my country and I did everything I possibly could to do it with honour,” he told the court.
“It breaks my heart actually.”
He described claims he committed multiple murders in Afghanistan as “devastating”.
In his evidence in chief, Roberts-Smith said he joined the SAS after serving with the Australian army in East Timor in 1999 and did six tours of Afghanistan from 2006 to 2012.
He said he’d always been “fascinated” by the military and that his family had a military history stretching back to Gallipoli and that included his father’s role as judge advocate general of the Australian Defence Force.
“It was something we took great pride in,” Roberts-Smith said.
The court heard he received multiple decorations across his military career including Australia’s highest military honour, the Victoria Cross, for actions as an SAS soldier at the 2010 Battle of Tizak in Afghanistan.
It was told that after leaving the defence force in 2013 he started a consulting firm and did internal work at the human resource department of accounting firm PricewaterhouseCoopers.
He is now on leave from his employer Seven West Media.
Earlier, the respondents’ barrister, Nicholas Owens SC, told the court none of the alleged murders at issue involved split second decisions in the “heat of battle” or the “fog of war”.
“We allege the victim was a PUC, a person under control”, Owens said.
He said the alleged killings did not involve even the “potentially fraught moments when a person is brought under control”, but were carried out because the victims were Taliban fighters.
He said the respondents would allege that Roberts-Smith’s accounts of the critical battlefield incidents included a “false narrative” to make it appear a person under control was killed in combat and a “deliberate lie” told to cover up an unlawful act.
“Your Honour will be asked to choose between two diametrically opposed stories,” Owens said.
He said there would be testimonial evidence from 21 current and former SAS members as well as several Afghan villagers that would show Roberts-Smith’s accounts were implausible, describing the witnesses as “honourable men”.
He said Roberts-Smith had engaged in a “pattern of behaviour” to undermine the case against him, including arranging “threatening letters” to be sent and the purchase of two “burner phones” so he could communicate without the fear of phone tapping.
On the alleged assault in Canberra, Owens referred to a text exchange between Roberts-Smith and a woman that the barrister said would assist in “demonstrating our truth defence is sound”.
Roberts-Smith’s legal team has so far depicted him at the trial as a courageous, self-sacrificial soldier who was devoted to duty but has been subject to a campaign of lying by “bitter people” and failed soldiers jealous of his military success and VC.
Bruce McClintock SC has previously described as ludicrous claims against his client including that he killed a “defenceless” Afghan with a prosthetic leg in an SAS attack on an insurgent compound in Uruzgan province.
The court has also previously been told that Roberts-Smith lost hundreds of thousands of dollars in income after his reputation as Australia’s most respected soldier was “smashed” by the media reports, and that he is seeking aggravated damages from the publishers.
The trial continues.