Gina Rinehart wanted a dispute with her son and daughter referred to arbitration. Photo: Michael Clayton-Jones
Billionaire mining magnate Gina Rinehart has lost a legal bid which would have prevented a bitter dispute over a lucrative family trust fund from being played out in a public courtroom.
Mrs Rinehart was hoping to have the dispute referred to private arbitration but Justice Patricia Bergin rejected the application on Wednesday and instead suggested the matter should go to mediation before a long-awaited trial.
Legal representatives for Mrs Rinehart's children John Hancock and Bianca Hope Rinehart agreed to mediation on the condition that a public trial would still be prepared.
Justice Bergin set down a three-day mediation session to occur later this month and, in the event that the session fails to resolve the family's high-profile dispute, a five-day trial in the Supreme Court in October which would see the dramatic saga reach its final climax.
Mrs Rinehart's children first filed a claim two years ago, alleging their mother acted "deceitfully" in her dealings with the family trust, set up in 1988 by Mrs Rinehart's father, Lang Hancock, with her children as the beneficiaries.
They claim she made changes to the trust in 2006 that prevented the children from being able to take their shares.
Mrs Rinehart, who is supported by her youngest daughter Ginia, has denied the claims.
She applied last week for the proceedings to be stayed and referred to arbitration, saying fresh claims made by the children fell under the terms of the family trust fund deed.
The court heard the two children "substantially" changed their case against their mother, putting forward a fresh claim that she changed the constitution of the family company, Hancock Prospecting Pty Limited.
Despite previously noting that the claim appeared to be "a new pleading, a new case", Justice Bergin dismissed Mrs Rinehart's arbitration application on Wednesday.
Barrister Christopher Withers, for Mr Hancock and Ms Rinehart, said his clients did not oppose mediation, but that it would have to take place after Mrs Rinehart's side produced documents they have been seeking.
The matter was due to return to court on Wednesday afternoon.