Australia's first convicted terror leader Abdul Nacer Benbrika will be held behind bars for another three years over concerns he remains a high-risk terrorist.
The self-proclaimed Islamic cleric who has expressed admiration for Osama Bin Laden was convicted in 2009 over his involvement in a terror group which plotted to kill non-believers to convince the Australian government to withdraw troops from Iraq.
Benbrika was sentenced to a maximum 15 years behind bars, and has been in custody since his 2005 arrest.
Supreme Court Justice Andrew Tinney granted a continuing detention order allowing authorities to hold Benbrika behind bars until November 2023.
Three years was the maximum the order could be made for.
He said Benbrika was a clear danger to community safety at he time of his offending and it was only through law enforcement intervention that potential mayhem and tragedy was avoided.
It was highly unlikely someone with Benbrika's narcissistic personality traits and sense of intellectual superiority would have changed his extremist views, Justice Tinney said.
Benbrika had claimed his views had changed in 2014, but the judge noted it was convenient he only mentioned that epiphany two weeks after parole was first denied in 2017.
"I am satisfied the defendant has not renounced or changed his previous beliefs, which justified terrorist violence in the name of Allah," he said.
Benbrika came to Australia from Algeria at 29 as a qualified aviation engineer, but Justice Tinney said he spent most of his time unemployed and focusing on advancing knowledge of his religion.
He began hosting classes about Islamic theology from about 2002, including for others convicted alongside him.
They discussed destruction of non-believers of Islam, intended to be achieved by acts of "terrible violence" with the intention of coercing the Australian government to withdraw troops from Iraq.
One expert determined Benbrika was a "high risk of violent extremism", and that he had a "grandiose self perception".
Another said he was still committed to an extreme Islamic ideology and expressed support for religious violence in conflict areas, including Somalia.
"He is considered to have a high likelihood of extremist behaviour that could promote and incite others in a violent extremist ideology," the expert said.
Justice Tinney said three less restrictive measures had been considered as an alternative to ongoing detention.
To have Benbrika surveilled 24-hours a day by police would be inadequate, and while cancelling his ex-citizen visa had some "superficial attraction" it would not be effective in preventing the risk he posed.
Benbrika's Australian citizenship was cancelled last month. He remains an Algerian citizen.
Home Affairs Minister Peter Dutton said where any person posed a significant terror risk to Australia, the government would do whatever was possible within the law to protect Australians.
