The claims were widely used by refugee advocates, the Greens, the medical profession and sections of the media to argue the case against returning a group of 267 asylum seekers to Nauru following a failed High Court challenge.
The ABC last week said the boy faced the prospect of being returned to the offshore detention centre where his attacker remained.
“There is no five-year-old child, it’s a figment,” immigration department secretary Michael Pezzullo told a Senate committee hearing in Canberra on Monday.
The department had followed up the claims with pediatrician Karen Zwi, who reported a boy had suffered serious mental health problems after an alleged sexual assault.
However, she did not say the child was five years old – or had been raped – as had been reported by the ABC.
Department official Cheryl-anne Moy told the hearing the child at the centre of the claims was more than double that age.
“The allegation was of a sexual assault from another child who was two years older – it was physical skin-to-skin contact,” she said.
“It wasn’t an allegation of rape.”
The committee heard the boy was now living in the community in NSW and receiving appropriate care.
Pezzullo criticised refugee advocates for making the claim and pointed to media advocacy “parading as journalism”.
Earlier, the immigration department chief took a veiled swipe at state leaders and churches who have offered support to the asylum seekers, saying that “yielding to emotional gestures” reduced the margin of discretionary action the department could exercise.
The group’s fate would be considered on a case-by-case basis when medical treatment in Australia was completed.
The Labor premiers of Victoria and South Australia have written to Prime Minister Malcolm Turnbull, offering to help resettle Australian-born asylum seeker children and their families. Other states including NSW and Queensland have also offered support.
Turnbull said the government had to be careful what signals it sent to people smugglers as it worked through a caseload inherited from the former Labor federal government.
“This is not an easy issue to manage, but it has to managed with a very cool head and a very big heart,” he told reporters in Canberra.
“If we give those people smugglers any marketing opportunity, let me tell you they will use it and there will be more deaths at sea, more children put at risk.”
Pezzullo said avoiding fanfare and gesture was crucial.
“The moment you have a chink of light, the moment you give someone a clue as to how to game the system, you will put people’s lives in danger.”
The Human Rights Law Centre, which last week lost a High Court bid to prevent asylum seekers including children and babies being sent back to Nauru, confirmed on Monday the child involved was not affected by the High Court ruling.
“The child at the centre of rape allegations is not a client of the Human Rights Law Centre and is not one of the 267 people linked to last week’s High Court challenge,” the HRLC said in a statement.
The HRLC also said it was not involved in the report of the alleged rape, aired on ABC television’s 7.30 Report on February 2.
“Neither the HRLC or (activist group) GetUp was involved in the decision to take the story to the media,” it said.
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