Mr Roberts-Smith arrived on home soil on Wednesday night for the first time since the decision in his failed defamation action was handed down.
He had been travelling with his girlfriend, Sarah Matulin, before arriving in Perth on a flight from New Zealand.
The former soldier was pictured relaxing in Bali as the Federal Court dismissed his defamation cases against The Age, The Sydney Morning Herald, The Canberra Times and three journalists over reports implicating him in war crimes in Afghanistan.
Justice Anthony Besanko found the allegations were substantially true, declaring Mr Roberts-Smith was not a reliable witness and had motives to lie about the events.
But on Wednesday the former soldier remained defiant and refused to apologise to the families of those killed in the incidents, adding that he was still weighing up an appeal.
"We haven't done anything wrong, so we won't be making any apologies," Mr Roberts-Smith told reporters at the airport.
"It was a terrible result and obviously the incorrect result.
"We will look at it and consider whether or not we need to file an appeal."
During a 2009 Easter Sunday raid on a compound codenamed Whiskey 108, Mr Roberts-Smith machine-gunned an unarmed prisoner in the back, taking the man's prosthetic leg back to Australia to use as a beer drinking vessel, the court heard.
Mr Roberts-Smith also stood silent as a rookie soldier was ordered to execute an elderly Afghan prisoner so he could be "blooded".
The ex-soldier later sent threatening letters to witnesses who ultimately gave evidence against him at the defamation trial after hiring a team of private investigators to find out their addresses.
Justice Besanko said those actions might constitute a criminal offence of attempting to pervert the course of justice or illegal use of a postal service.
Mr Roberts-Smith quit his job as general manager of Seven Queensland following the court ruling.
Seven West executive chairman Kerry Stokes had financially backed the defamation case.
