The IBAC hearing into corruption in the Education Department has been told it was easy to spot false invoices prepared by sacked executive Nino Napoli because he could not spell.

The Independent Broad-based Anti-corruption Commission (IBAC) hearing has been shown multiple false invoices to the Department of Education allegedly prepared by the disgraced former director of school resources.

"It's easy to tell which false invoices have been prepared by Nino Napoli, because he can't spell," counsel assisting the inquiry, Ian Hill QC, told the hearing.

"He might be involved with the Education Department but he can't spell."

The IBAC investigation has tendered multiple emails and invoices from Mr Napoli with spelling and grammatical errors including; "buisness", "traing", "pamplett" and "Printing and Stationary".

The hearing has been told Mr Napoli regularly prepared quotes and invoices on behalf of businesses run by his cousin Carlo Squilliacioti.

Mr Hill said the invoices falsely prepared by Mr Napoli consistently spelt Carlo with a K and had bogus tax invoice numbers that bear no resemblance to the tax invoice numbers prepared by the business owner Mr Squillacioti.

At the hearing, Mr Hill asked Mr Squillacioti whether Mr Napoli ran his business, Customer Training and Consulting.

"Seems like Nino Napoli is effectively running your company," Mr Hill said.

"Yes it looks like that," Mr Squillacioti replied.

"You can't invoice people for goods and services you didn't provide," Mr Hill said.

"People do things like that, let's face it," Mr Squillacioti replied.

"You get complacent sometimes," Mr Squillacioti said about his record keeping.

At the hearing, Mr Hill told Mr Squillacioti: "You understand it's a clear fraud and you're part of it don't you?"

"No, not really," Mr Squillacioti replied.

Mr Hill said there was "transaction after transaction where there were no goods provided or services rendered."

"It's a lot clearer now," Mr Squillacioti replied.

Fears over discovery of spreadsheet of transactions

The hearing was played conversations recorded at Cobra Motors, a car shop run by the Squillacioti brothers.

In it, Mr Napoli can be heard fretting about the possibility investigators could discover Mr Squillacioti's spreadsheet of transactions.

Mr Napoli told Mr Squillacioti to destroy the spreadsheet.

"If you've got that you might as well put me in jail," Mr Napoli said.

Mr Hill asked Mr Squillacioti where the spreadsheet is.

Mr Squillacioti said he did not know: "I couldn't go straight to it but it's gotta be around somewhere."

His brother, Luigi Squillacioti, also expressed concern about going to jail in a recorded conversation.

"I've got to feel, as much as I fucking hate to think it, I reckon that Nino's gonna do time and I reckon Carlo's going to go in," he said.

"I reckon I could fucking go in as well."

Carlo Squillacioti has admitted creating a false paper trail with Mr Napoli to try to justify hundreds of thousands of dollars of Department of Education payments to businesses he owns.