Allan Keith Huggins, 77, was found guilty in August on 36 counts of molesting 10 young male patients in Armidale, in northern NSW, between 1977 and 1986.
The victims of those crimes were forced to wait more than a decade for Huggins to finish serving a prison sentence in Western Australia, before he was extradited to NSW to face justice.
In 2015, a WA jury had found he had abused seven boys while working as an education officer in a school-to-work program in 1990 and 1991, and he was sentenced to nine years in jail.
Crown prosecutor David Patch told a sentence hearing in Sydney's Downing Centre District Court on Tuesday, there was a "multiplicity of other offending, on other occasions" for which charges against Huggins have never been brought.Â
"Your Honour would accept ... there were in fact many other such events," Mr Patch said
The abuse in NSW took place at a youth centre for troubled boys, as well as at a school and at Huggins' own private practices.
Huggins used his position as a counsellor to gain access to victims he knew were vulnerable, including those with behavioural issues or from dysfunctional family backgrounds, Mr Patch told the court.
"They were almost always children in particular need of care," he said.
"Need of care from the offender."
Mr Patch told the court in one of the instances the victim was put under hypnosis and his clothing was removed, before being abused.
"He was naked and powerless," Mr Patch said.
In another instance in which Huggins penetrated his victim he told them it was painful to prepare them for a trip to the dentist the following day.
"The offender caused that pain deliberately," Mr Patch said.
Mr Patch told the court the impact on the victims of coming forward that they were abused is considerable, particularly given some were not believed.
"More than one tried and were not believed by the Catholic Church, by the school and by the police," he said.
Huggins listened silently from the dock taking notes on a pad as the parties discussed his fate.
The hearing continues.
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