Porter's appeal is a 'matter of principle'

Christian Porter's appeal against a court decision preventing a barrister acting for him was not just about his legal bill but also a "matter of principle", a judge has been told.

The former attorney-general and defamation barrister Sue Chrysanthou SC face a potential costs bill of more than $500,000 after losing a legal battle with a friend of the woman who alleged she was raped by Mr Porter in 1988.

He has emphatically denied the allegation

The friend, Jo Dyer, succeeded in her Federal Court lawsuit in preventing Ms Chrysanthou acting for Mr Porter in his defamation proceedings against the ABC.

Justice Tom Thawley found Ms Dyer had given the barrister confidential information potentially relevant to the defamation case and ordered Mr Porter and Ms Chrysanthou to pay her legal costs.

An appeal by Mr Porter, who has since settled his case with the ABC, is expected to be heard in February.

In a brief case management hearing on Friday, Mr Porter's barrister Callan O'Neill was asked by Justice John Middleton did it amount to a fight about costs.

While in one way it did, Mr O'Neill said "it is also a matter of principle".

The way the case had been conducted involved very important matters about how an application of this type should be made and heard in future, he said.

The judge said he was going to make a suggestion if it was just an issue of costs, but noted Mr O'Neill was saying it went beyond that to a matter of principle.

"Although often matters of principle go away when sufficient money is paid over," Justice Middleton said.

While Mr O'Neill said he did not hold out much hope that mediation would succeed, the judge said he could make an order for the registrar to assist if all the parties wanted to avail themselves of that process.

Mr Porter resigned as the federal minister for industry in September after failing to explain who was behind an anonymous "blind trust" donation to pay for his defamation case.