Western Cape Deputy Judge President Jeanette Traverso has been accused of misconduct in Shrien Dewani's trial because she was an "Afrikaner" and a former "apartheid prosecutor" - and therefore "predisposed towards showing hostility against the black prosecutor, who was up against the all-Afrikaner defence team".
These claims are contained in a complaint the non-profit organisation the Higher Education Transformation Network has lodged with the Judicial Service Commission.
British businessman Dewani was accused of orchestrating the murder of his wife, Anni, while on honeymoon in Cape Town in November 2010 but he was discharged last month after the prosecution closed its case.
The group's chairman, Lucky Thekisho, said Traverso failed to afford the state a fair hearing.
The group wants the commission's Judicial Conduct Committee to recommend the establishment of a judicial conduct tribunal to consider the allegations against Traverso.
In his affidavit, Thekisho said Traverso failed to disclose her friendship with the defence counsel. Thekisho said Traverso treated the defence team with courtesy but she harassed and aggressively interrogated the prosecution team.
Said Thekisho: "Through her repeated demeanour, she sought to intimidate, undermine and speak down to the prosecution. This occurred because of her hostility and her bias in favour of the defence."
Thekisho said while the complaint was not directed at Traverso's ruling, it maintained the judge presided over the Dewani trial in an inept manner.
"Creating an appearance of favouritism towards one party constitutes grounds for disciplinary proceedings against a judicial officer," Thekisho said.