$20m fraudster splashed cash on prostitutes, race horses Damian O'Carrigan with his wife Julie at the opening of Leighton's new Brisbane office in 1986. A trusted finance manager who defrauded national construction giant Leighton Contractors of more than $20 million has been sentenced to 15 years behind bars. Despite earning a six-figure salary, Damian Victor O'Carrigan, 58, systemically defrauded his employer over a 12-year period from May 2000 to fund an opulent lifestyle. In the Brisbane District Court on Friday O'Carrigan was sentenced to three charges relating to the fraud, which was only discovered by his employers during a cost-cutting audit in November last year. Damian O'Carrigan. Crown prosecutor Todd Fuller told the court O'Carrigan's "audacious" theft was based on "greed rather than need." O'Carrigan splashed the funds on race horses, calls girls and properties. The court heard O'Carrigan felt exploited by his employer and was pressed for money when he set about defrauding the construction giant. In May 2000, O'Carrigan established a dummy consultancy company, Acorn Cottage, which was also the name of a Tasmanian farmhouse O'Carrigan and his wife intended to retire to. He first billed Leighton Contractors $28,000 for consultancy services on May 30, 2000. Over 12 years, he issued 308 invoices from Acorn Cottage to his employer, fleecing the company of more than $20.7 million. The invoices, which O'Carrigan lodged fortnightly and sometimes weekly, ranged in amount from $10,000 to $205,000. Within days of receiving the payments, he transferred the funds from an account registered to Acorn Cottage to his own. He spent close to $7 million on horses in Australia and New Zealand worth far less than their monthly upkeep of $75,000, the court heard. He also paid for his mistress to travel to the Netherlands and the United States to purchase two thoroughbreds. His mistress, for whom he purchased a rural property, also had unfettered access to a credit card O'Carrigan paid on her behalf. "It's clear it was a scheme from the outset," Mr Fuller said. Barrister Michael Byrne, QC, acting for O'Carrigan, stressed his client's cooperation with authorities should be viewed as a mitigating factor in his sentence. Mr Byrne said O'Carrigan's wife of 30 years and his adult daughter had suffered deep shame and stress since the case was widely publicised. In sentencing the disgraced finance manager, Judge Nicholas Samios said O'Carrigan was deserving of the maximum penalty for his offences. "You performed no services for those monies you received," he said. What makes your offending so serious is not only was there a breach of trust and that it persisted over a period of 12 years and that it was for such a substantial sum of money, is that the likelihood of recovery is such that there will be a large shortfall. Judge Samios said $4 million could be recovered at best, leaving Leighton Contractors with a loss in the order of $16 million. "This case does fall within the worst category of offending," he said. It's also correct to state that what you did over that 12-year period and what you spent [the money] on is outrageous. O'Carrigan had pleaded guilty to the charges. He will be eligible for parole in six years. Outside court, O'Carrigan's solicitor issued a public apology on his client's behalf. Peter Shields said O'Carrigan wished to publicly apologise to his wife Julie for the shame he had brought upon her. "He genuinely means that," he said.