The duo then melted the gold and resold it as a powder to Melbourne company Focus Gold.

They then claimed they had paid taxes on the initial purchase and requested a tax offset from the Australian Taxation Office.

Later that year the pair roped in family and friends and placed them between themselves and the pure gold sellers to avoid suspicion, and make it seem as if they were buying secondhand - therefore being forced to pay tax on the gold.

The scheme took a different approach in 2013 when the pair recruited people they referred to as "Koreans" or backpackers on working visas to be the middlemen between them and the sellers.

The ATO ultimately refunded them more than $40 million in tax offsets before they were arrested and charged in 2018.

Millner, who now works and volunteers as a disability support worker, was refused bail on Thursday despite his lawyer arguing his clients could not cope without him.

"There is of course no greater work in the community than people who volunteer to help those who need it," Justice Richard Cavanagh said in the NSW Supreme Court on Thursday.

"However, it is a sad reality that when people commit serious offences and they go to prison, the people that suffer the most are the people left behind."

Two of his clients, one in a wheelchair, sat at the back of the court and became emotional when the verdict was read out.

Kelu, who ran as a candidate for former prime minister Malcolm Turnbull's seat of Wentworth in 2007, was granted bail to receive treatment for lead poisoning.

The judge said he accepted that Kelu's heavy metal toxicity and his "undisputed autism diagnosis" amounted to special circumstances.

Justice Cavanagh said both men would be "sentenced to a term of imprisonment" but it was important that when they enter custody their "physical and mental health are as good as they can be".

He did not indicate how long the jail term would be though the pair are set to be sentenced on October 5.