Christian Porter and barrister Sue Chrysanthou ordered to pay costs to Jo Dyer

A judge has made a decision that will be unwelcome for a lawyer that acted on behalf of Christian Porter in his defamation suit against the ABC.

Christian Porter and his barrister have been ordered by a judge to pay costs associated with a court case brought by a friend of the woman who accused the former Attorney-General of raping her three decades ago.

The woman, Jo Dyer, had sought a court order preventing Mr Porter’s high-profile barrister Sue Chrysanthou from acting on his behalf in a separate case, a defamation action brought by Mr Porter against the ABC.

Mr Porter, who denies the rape allegation, and Ms Chrysanthou will have to pay the costs of the proceedings brought by Ms Dyer.

Ms Dyer brought the case to the Federal Court attempting to prevent Ms Chrysanthou from acting for Mr Porter over what she said was a conflict of interest.

Christian Porter has had a costly setback in court. Picture: Matt Jelonek/Getty Images

Ms Dyer said that Ms Chrysanthou had previously advised her in relation to her friend, known as Kate, who died last year before she could give a formal police statement about her accusations against Porter.

Justice Tom Thawley sided with Ms Dyer in late May.

With Friday’s judgment, Justice Thawley settled the question of who should pay for the proceedings.

He dismissed arguments by both Mr Porter and Ms Chrysanthou that they should not have to bear the full costs.

“In the circumstances of this case, my view is that Ms Chrysanthou should not be relieved of an order that she pay the costs of the successful party,” Justice Thawley wrote in the decision.

While the judgment did not specify how expensive the payment would be, it noted that Ms Chrysanthou’s solicitors had “adopted an adversarial approach” before Ms Dyer launched her case, “including threatening an application for security for costs in the amount of $150,000 should proceedings be commenced”.

Mr Porter dropped his defamation lawsuit against the ABC on May 31.