Adam Cranston, 36, was sentenced on Tuesday to 15 years with a non-parole period of 10 years for his role in the $105 million Plutus Payroll tax fraud and money-laundering conspiracies.

He was found guilty in March along with four others, including his younger sister, following a marathon trial beginning in April 2022.

They conspired to cause a loss to the Commonwealth and deal with the proceeds of crime between March 2014 until their arrests in May 2017.

Cranston is the son of former deputy taxation commissioner Michael Cranston, who was cleared in 2019 of any involvement in the scheme.

The group used Plutus Payroll and its web of second-tier companies, which were directed by vulnerable dupes, to siphon off funds that should have been paid to the tax office.

Justice Anthony Payne rejected any suggestion Cranston was misled over the scheme, labelling as “preposterous” suggestions the conspirator thought Plutus was a profitable company.

“He was involved in the inner workings of the conspiracy and knew at all times that Plutus was not legitimate or profitable,” he said as he sentenced Cranston in the NSW Supreme Court.

Plutus’s legitimate clients were not informed about the firm’s use of the second-tier companies as part of the scam.

“This is because it was a mechanism designed to misappropriate amounts that should have been paid to the ATO,” Justice Payne said.

Those firms were directed by “vulnerable, unsophisticated” people who did not understand them, while the companies were truly controlled by the conspirators.

Cranston personally received more than $6.8 million for his efforts in the fraud, the scale of which he boasted about in a covert recording.

“If this was fully uncovered and they knew exactly what was going, on it’d be f***ing Ben Hur, man,” he said in one intercepted conversation.

Australian Federal Police assistant commissioner Kirsty Schofield said the recordings made for “concerning” listening.

“The degree of how they were blasé about it, the level of deception, it was really uncomfortable to be honest,” she said outside court.

Justice Payne branded Cranston’s crimes “corrosive”, amounting to a collective financial injury to the whole community.

“Honest taxpayers are left with a legitimate sense of grievance, which is itself divisive,” he said.

Taxes were the price of a civilised society and the money should have been available to pay for schools, hospitals, “and perhaps pointedly in this case, Legal Aid,” Justice Payne said.

Cranston’s sentencing was delayed in May due to the withdrawal and eventual reinstatement of commonwealth funding for his legal representation.

Justice Payne said Cranston acted out of greed and made no real attempt at contrition.

Rather, he appeared to still believe he and his co-conspirators had done nothing criminal, failing to understand the “gross violation” of societal norms he perpetrated.

Cranston appeared on-screen from custody, where he has been since being found guilty in March.

He will be eligible for release in March 2033.

Justice Payne will also sentence former professional snowboarder Jason Onley, 53, another architect of the conspiracy, on Tuesday.

Along with Cranston, he controlled the second-tier companies forming the “engine” of the scheme, the judge said.