Former Dual Australia claims manager Josie Gonzalez was the mastermind behind a $17.4 million fraud that could have destroyed the underwriting business, County Court of Victoria Judge Paul Lacava said today before sending her to jail.

Judge Lacava sentenced Josie Gonzalez to 9.5 years in prison and her husband Alvaro to 7.5 years after a jury in July found them guilty of 14 charges of obtaining a financial advantage by deception.

“The prosecution case that this was a joint criminal enterprise between the two of you was in my view unassailable,” he said. “But your role, Josie Gonzalez, was as the principal offender.”

Josie, 45, will serve a minimum seven years before being eligible for parole, while Alvaro, 51, will serve a minimum five years.

The couple began falsely billing Dual a few months after Josie joined the company in November 2010. Some 428 invoices were submitted from Jaag Lawyers, a firm they set up to carry out the crime. “Jaag” is an acronym of Josie and Alvaro Gonzalez.

Judge Lacava said the Dual fraud took place over a prolonged period and escalated over time, with the offending “of a very high level for a fraud of this kind”.

“The money that you obtained from your fraud, while it came to Jaag from Dual, was in fact money held in trust by Dual for its Lloyd’s syndicates in London,” he said. “What you did had the potential to destroy the business of Dual.”

Gonzalez had maintained that Dual CEO Damien Coates had told her to “go for it” when she spoke to him about her plans to set up a firm with Alvaro to provide legal services.

“That in my judgment was a blatant lie and would have been seen as such by the jury,” Judge Lacava said.

The greater severity of Josie’s sentence took into account that she had pleaded guilty to deception in a magistrates’ court when she was 22 and a salesperson at Myer in the Melbourne suburb of Highpoint West. The case involved 51 instances of falsifying vouchers related to customers returning goods. She received a good behaviour bond, but escaped conviction.

Josie Gonzalez was later admitted as a legal practitioner despite the board of examiners knowing of the earlier court case. Alvaro was admitted in 2009.

The “remarkable similarity” between the previous case and the Dual fraud showed she did not learn her lesson, Judge Lacava said, assessing her prospects for rehabilitation as “only fair”.

He described most of her evidence as a “concoction of lies”.

Judge Lacava said he believed Alvaro had been encouraged into the deception by his wife, but had also played an active role in supporting the fraud and had benefitted from the proceeds, including through the purchase of a $4.7 million property in the upmarket suburb of Kew.

“I conclude that you both lived very well on the proceeds of the fraud at the expense of Dual before being caught out.” Neither of them was remorseful, he noted.

Some of the charges involve claims of more than $50,000 and carry a maximum penalty of 20 years.

Judge Lacava said Dual was repaid the stolen funds and he had applied some “mercy” as the couple have two daughters aged six and 11 who are being cared for by relatives.

The full recovery of proceeds, which included money paid to the tax office, followed settlement of a civil deed brought by Dual in September 2013. The agreement released the parties from any further civil action.

But a criminal case was launched after the crimes were reported to police in November 2013 by the Legal Services Board, which is responsible for regulating the legal profession.