Mr Porter appealed the disqualification of barrister Sue Chrysanthou SC and around $500,000 in potential legal costs after losing a legal battle against the friend of a woman who alleged he raped her in 1988.
That friend, Jo Dyer, consulted with Ms Chrysanthou about a potential defamation claim against News Limited for an article in The Australian in November 2020 and provided confidential information to the barrister which was potentially relevant to Mr Porter's lawsuit against the ABC, Justice Tom Thawley found in May last year.
Mr Porter launched defamation proceedings against the ABC over publications containing the historical rape allegations, despite not being named within the articles.
Days after Justice Thawley ordered Ms Chrysanthou to step down, citing the potential for the misuse of confidential information, Mr Porter dropped his lawsuit against the ABC.
On Thursday, the Full Court of the Federal Court dismissed Mr Porter's appeal, putting him on the hook for hundreds of thousands of dollars in costs.
At an appeal hearing in April, Mr Porter's barrister Bret Walker SC argued there was no rule letting a barrister refuse a brief because it was "embarrassing" and pointed to the so-called cab rank rule which he said required Ms Chrysanthou to act for Mr Porter when he approached her in March 2021.
Ms Dyer's barrister Michael Hodge QC said Justice Thawley's findings should hold because of the potential for the subconscious misuse of confidential information within the defamation proceedings.
Ms Chrysanthou, through legal counsel Anne Horvath SC, rejected claims she misunderstood her professional obligations or planned to deliberately misuse the court's processes.
