The notorious paedophile last month found again to have abused young boys will remain in the nursing home where he lives with debilitating and irreversible dementia and Parkinson's disease.
Justice David Mossop on Friday said neither the prosecution nor the defence said it would be appropriate for 87-year-old John "Kostka" Chute to be taken into custody.
The judge also said custody would not be appropriate given his age, health and personal circumstances, as well as the absence of any risk to the community.
Chute, also known as Brother Kostka, faced 16 charges as against six victims between 1979 and 1986.
There were 14 counts of indecent assault of a minor, one charge of buggery without consent and one charge of an act of indecency with a minor.
Brother Kostka had been found unfit to plead and faced a special hearing by judge alone.
Late last month Justice Mossop returned not guilty verdicts on the count of buggery and a count of indecent assault.
All other abuse had been perpetrated as alleged, the judge found.
But because Kostka had been found unfit to plead there was no finding of guilt nor conviction.
The judge also said there would be no use in requiring Kostka to submit to the ACT Civil and Administrative Tribunal to allow it to make any mental health order.
"Mr Chute is 87 years old and lives in New South Wales in a nursing home. He suffers from dementia. His dementia is progressive and irreversible," Justice Mossop said.
"He suffers from a constellation of health problems ... [h]e rarely leaves the nursing home. The possibility of further offending conduct is negligible.
"The capacity to improve his circumstances by measures to address his mental health will not be added to by the making of any orders by the ACAT."
He added that no order would serve to protect the community, improve the health or safety of Kostka and would simply divert the tribunal's resources for no useful purpose.
Kostka had pleaded guilty in 2008 to a large number of historical sex abuse charges as against 19 children and spent at least two years in jail.
His case was the subject of hearings at the Royal Commission into Institutional Responses into Child Sexual Abuse.
Those hearings were told the Marist Brothers had received at least 48 complaints from as early as 1959, and from six different schools, before Kostka was finally jailed.
By 2014, the Marist Brothers had paid out $6.84 million in compensation to 38 former students in connection to Kostka.