Lawyers for two Kalgoorlie men on trial over an alleged million-dollar gold theft have told the District Court they were duped into participating in the alleged fraud of miner FMR investments.

Russell Wilson Holden, 51, and his business partner, Simon Leslie Gash, 57, are fighting money laundering and fraud charges as part of the trial, which is now in its third week.

Patrick Rhyan Keogh, 42, the former general manager of FMR Investments, and former Greenfields Mill manager Christopher Robert Burns, 76, have both pleaded not guilty to stealing as a servant and other charges relating to the proceeds of an offence.

The charges relate to the alleged theft of 8,465 tonnes of gold-bearing ore from the Greenfields Mill, owned by FMR Investments, between December 2018 and January 2019.

Based on metal prices at the time, the gold the ore produced had an estimated value of $1.17 million.

Mr Keogh has maintained that FMR Investments founder, well-known WA mining entrepreneur Peter Bartlett, gave him permission to profit from the ore, referred to as the "clean-up pile", during a conversation a decade ago. 

The court has heard that material mined by Mr Holden and Mr Gash was combined with the allegedly stolen ore to make a bigger parcel for a milling campaign.

'Unwitting bunnies'

In his closing address, Mr Gash's lawyer David Grace KC told the court that the business partners were the "unwitting bunnies" in the case.

He said the pair were "not privy" to discussions between Mr Keogh and Mr Bartlett and were "entitled" to believe that the company's general manager and mill manager were authorised to act as they did.

"There was no earthly reason for them to believe otherwise," Mr Grace said.

"They have been dragged into this case … they're the unwitting bunnies in all of this."

Mr Grace reiterated that there was no evidence of fraud and said his client had an obligation to pay Mr Keogh and Mr Burns, so he did.

"The prosecution will tell you they must have known [about the allegedly stolen ore], but there's no evidence of that," he said.

"There's nothing to prove they would descend to fraud … it's a giant step to conclude they went out to defraud.

'Above board'

Mr Holden's lawyer Paul Yovich told the jury that his client had no reason to believe that the campaign was anything but "above board".

"[Mr Keogh] tells them that, they act on good faith, it's a handshake agreement," Mr Yovich said.

"If there's any deceit going on, [Mr Holden and Mr Gash] are deceived.

"They had no reason to believe it was anything other than an above board, arm's length, gentleman's agreement going on."

The prosecution alleges the business partners knew about plans to combine the ore and defraud FMR Investments of its share.  

Mr Yovich told the jurors the case hinged on whether they believed Mr Keogh's testimony or that of his former employer, Mr Bartlett.

"If [Mr Keogh] didn't [steal the ore], and if you're satisfied beyond a reasonable doubt, that's the end of it," Mr Yovich said.

"Mr Holden will have committed no offences, and that's the same for the other co-accused."

He later added: "If Mr Keogh is acquitted of count one [the charge of stealing as a servant], everyone goes home".

'Human nature'

Mr Yovich said there was no evidence to support the prosecution case against Mr Holden.

"There is a gap … and the state is no Evel Knievel," he said.

Mr Yovich told the jury to view Mr Holden's December 16 2020 police interview with the knowledge that he had spent five hours in a cell before it began at 7pm.

The court also heard that his wife had been arrested that same day because she was a director of one of his companies, but she was later released without charge.

State prosecutor Paul Usher used his closing address to describe the nature of the group's dealings as "nefarious" and surreptitious".

Mr Usher spoke briefly on Thursday morning about "financial gain" as a "possible motive" for the offending.

"It's human nature to look for a reason to explain why someone has done what they've done," he told the jury.

"On the evidence, it is open for you to find Mr Keogh and Mr Burns had financial gain borne out of an opportunity to use the clean-up pile for their own use."

Defence lawyers for the remaining  co-accused will make their closing arguments on Friday.