A man seeking to represent participants in a battle involving the Golden Sphere Pyramid scheme has a record as one of Queensland's most colourful conmen.

Last week The Sunday Mail revealed the Australian Competition and Consumer Commission planned to allow up to 10,000 participants to jointly sue the scheme's organisers.

But a so-called "legal advocate" claiming to represent up to 5000 of the scheme's participants is Donald James Cameron, 53, a man with more than 20 criminal convictions spanning 35 years.

Cameron has been convicted of unlawful assault of a female, of being a bogus doctor, forgery, uttering, and stealing, and of several counts of false pretences.

He has posed as a doctor and a lawyer, acted as a pastor and has appeared to fool media, a former Attorney-General, the Queensland Corrective Services Commission and the courts.

Last week the organisation The Citizens for Financial Independence Association wrote to the Federal Court claiming the scheme's participants were opposed to the commission's move to sue Golden Sphere's organisers.

The letter was signed by Don Cameron: "President - Legal Advocate'', and was faxed to the media.

Yesterday, Mr Cameron told The Sunday Mail that all members of his association were aware of his criminal past.

"There's not a person in this country who is not aware of my background and I don't hide it, I lead with it.

"I'm not ashamed of anything I've done.''

He claimed he held a law degree, was a legal advocate, but could not practise as a solicitor because of his criminal history.

State Government officials have said courses Cameron attended in prison were mostly computer-related and not law. They could not confirm a claim by Cameron that he had completed a US law degree by correspondence.

In 1993 Cameron made national headlines as an adviser to rebel farmers George and Stephanie Muirhead and was credited with suggesting they secede from Australia.

Cameron represented the Muirheads in court and gave them legal advice while he was a prisoner, living at the St Vincent De Paul Society home in South Brisbane while serving a four-year sentence.

He was released from prison in March, 1994, but two months later got a Brisbane local newspaper to publish a report saying he was a clergyman with a law degree who wanted to build a legal centre for Beenleigh youth.

On March 5 this year, the Queensland Court of Appeal declared Cameron a vexatious litigant.