NAB 'embarrassment a factor in fraud case'

The lawyer for the alleged mastermind of a multi-million fraud perpetrated against the National Australia Bank says it's an enormous assumption that NAB leaders had no idea where its money was going.

Events management company executive Helen Mary Rosamond has pleaded not guilty to dozens of bribery and fraud charges over her alleged dishonest use of bank funds to support a life of luxury for Rosemary Rogers.

Rogers, the now-convicted former chief of staff to the National Bank of Australia's chief executive, told the trial she received a house, a BMW car, a boat, holidays and other benefits after approving false bank invoices for Rosamond between 2013 and 2017.

But Rosamond's barrister on Wednesday attacked Rogers and the bank, particularly over the apparent lack of independent checks on spending by the chief executive's office.

"Isn't it somewhat unbelievable that leaders of this organisation of 30,000 employees, who'd risen to the top of the corporate ladder ... could be so unbelievably lax or grossly negligent that they have no idea what they were spending their or their customers' money on?" barrister Anton Hughes asked jurors in the NSW District Court.

"That's one enormous assumption you are being asked to make."

Dr Hughes said the "simple truth" was that once police were involved, that NAB had tried to save face in light of "the resulting embarrassment to them".

He said NAB had signed fixed-price contracts with events and human resources company Human Group, which lacked an agreement to refund unspent money.

Rogers may have felt it was obvious where payments for various luxuries were coming from but there was no direct evidence of an agreement to defraud between her and Rosamond, the Human Group chief executive.

"(Rogers') perception is a justification to make her feel less guilty about what she did," Dr Hughes said.

Jurors were asked to consider dismissing everything Rogers said.

"She is demonstrated and accomplished liar," Dr Hughes said.

"She successfully deceived her employer for a period of at least five years, managed to mislead everyone she worked with, lied to her family ... took her sister's money and kept it, lied to executives at the bank ... lied for no apparent reason."

Rogers created forgeries in the names of her former boss Andrew Thorburn and her in-laws.

"Now, the Crown says she came before you to give an honest account," he said.

The Crown has detailed how Rosamond allegedly paid for Rogers and her family to fly off on trips within Australia and overseas.

The amounts were charged to NAB through allegedly fraudulent, altered invoices so the bank and staff at Human Group were none-the-wiser.

"This is the way the accused ensures that Rose Rogers stays onside, stays happy, and continues to get her benefits which ... Ms Rogers said she'd become dependent on to maintain her lifestyle," crown prosecutor Katrina Mackenzie told the court in closing submissions.

Payments included $7500 for a trip to Fiji, $40,000 for a weekend at Sydney's Park Hyatt, and $21,000 for Roger's relatives to fly to Broome in Western Australia.

The trial continues.