Raban Alou has been sentenced to 44 years behind bars for obtaining a revolver and handing it to Farhad Jabar Khalil Mohammad, who then used it to shoot dead police accountant Curtis Cheng.
And after the sentence was given on Thursday morning, Alou stood to be led away by corrective services staff and made an Islamic State salute towards the back of the courtroom as he said "this is the beginning" and spoke in Arabic.
Mohammad, 15, walked closely behind Mr Cheng as the father of two left police headquarters in Parramatta on October 2, 2015. The teenager shot him in the head, killing him instantly, before he was shot dead by special constables.
The gun had been given to him that afternoon at Parramatta Mosque by Raban Alou, then 18, who had become increasingly radicalised and obsessed with the "poisonous and criminal views" of the terror group Islamic State.
Alou, 20, was sentenced to a maximum of 44 years behind bars, with a non-parole period of 33 years, at the NSW Supreme Court in Parramatta on Thursday after he pleaded guilty to aiding, abetting, counselling or procuring a terrorist act.
Justice Peter Johnson said Alou was "a key person who played a lead role" in the criminal enterprise, which was of a "very high level of objective gravity".
He said the crime could not have been committed without Alou, who has never shown remorse for what he has done, has shown no interest in prison deradicalisation programs, and has not apologised to Mr Cheng's family.
Raban Alou pleaded guilty to obtaining a revolver and handing it to Curtis Cheng's killer.
Photo: Supplied"The offender's response is devoid of basic humanity," Justice Johnson said.
"It is clear the offender remains dangerous to the general community given his views."
The prospects of rehabilitation for Alou are "grim", with his views "deeply entrenched".
Curtis Cheng was shot dead as he left work on October 2, 2015.
Photo: NSW Police MediaPart of this entrenched behaviour included refusing to stand when Justice Johnson entered the courtroom. Alou again remained seated during his sentencing on Thursday.
"It is not possible to decide at this point that his prospects for rehabilitation are anything but bleak," Justice Johnson said.
Without a 15 per cent discount for Alou's guilty plea, he would have been imprisoned for a maximum of 52 years.
Justice Johnson said Alou's outburst as he was led away was further proof his his lack of contrition.
"He gestured to persons in the back of the court in a manner which indicated the strong and continuing existence of poisonous fundamental views," Justice Johnson said.
"What I have just said should also be taken into account by those who have to make a decision in respect to parole at any time in the future."
Speaking outside court, Mr Cheng's wife Selina and son Alpha said they were satisfied with the judgment.
"We really hope it sets a strong precedent about how actions like this and hate and tolerance is really not respected or condoned in Australia," Alpha Cheng said.
"We hope that things we had to go through as a family never happens to anyone in Australia."
Curtis Cheng's son Alpha Cheng and widow Selina Cheng speak outside the court
Photo: AAPHe said comments by the judge - acknowledging the family's strength and courage in contrast to Alou's "wickedness" - were "touching" and gave them further strength to continue their healing.
The sentence was the first time the charge of aiding and abetting a terrorist act had come before a sentencing court in Australia.
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