More than a dozen teenagers will spend at least one more weekend in jail, with a Supreme Court judge reserving his decision on whether their incarceration at Barwon Prison is legal.
But a lawyer for the government caused ripples in the courtroom by seeking to justify their detention, claiming that even though the teenagers being held in isolation in adult are "still legally children, while they are not cognitively and psychologically mature, these young people have the size and strength of men; they are physically mature".
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Juveniles face adult prison after Parkville riots
Forty juvenile offenders over the age of 16 face adult prison following riots at the Parkville detention centre, but the government can't say which facility the youths will be sent, or for how long. Courtesy ABC News 24.
The Victorian government last month began transferring children from three youth justice centres to the maximum security prison after the riots that caused about $2 million damage at Parkville.
A challenge to the legality of that move concluded in the Victorian Supreme Court on Thursday.
In an at-times fiery hearing, Melinda​ Richards, SC, acknowledged that it was confronting to think of children being held in isolation in their cells at the maximum security prison.
"There is no doubt that it is confronting," she said, "but just because it is confronting does not mean that it is an abuse of human rights".
She said the use of isolation was "strictly regulated", to be used only as a last resort, and served to prevent young people from harming themselves or others.
"We're talking about 16 and 17-year-old boys, we are not talking about young children," Ms Richards said. "Against that context it is perhaps less confronting to consider that a 16 year old or 17 year old might be placed in isolation."
Most of the young people held at Barwon had been charged with serious criminal offences, Ms Richards said.
However, the court has previously heard that none of the children at Barwon have yet been convicted of the crimes of which they are accused, meaning they could yet be found not guilty.
Lawyers acting for the boys being held in the repurposed Grevillea unit within the prison argue that the minimum standards of care required to detain children were not met when they were transferred from the Parkville and Malmsbury youth justice centres, and a temporary centre set up at the Mill Park police station.
Brian Walters, QC, for the teens, told the court on Thursday that it was not enough for the government to say that conditions had improved.
The environment at Barwon is, he said, a "chaotic, high-stimulus environment where Corrections staff could be deployed at any time, and where parents won't be able to visit for some time".
"Things are getting better. But either [repurposing the unit as a youth justice centre] was lawful or it was not; and either the transfer decisions were lawful or they were not."
Ms Richards said that given the level of damage done to Parkville in the riots, the department's secretary had been "struggling to meet her requirement to provide basic standards of accommodation".
But Justice Gregory Garde said: "But even accepting that it is an emergency, does that mean you pay less attention [to the human rights of children] ... or is it a more demanding requirement of proper consideration, because you're in a very difficult, demanding and even extreme situation where human rights are seriously at risk?"
The government should have a contingency plan if the court found the children had been transferred to Barwon unlawfully, Mr Walters said, as their detention at Barwon would "at that moment" be unlawful.
Justice Garde will hand down his decision at a later date.