Former US president Donald Trump and other defendants in Georgia’s election interference case filed court papers on Monday seeking to appeal against a judge’s ruling not to disqualify Fulton County district attorney Fani Willis from their prosecution.

The resignation of the special prosecutor with whom Ms Willis had a romantic relationship is not enough to correct the appearance of impropriety the judge found, lawyers for Mr Trump, former New York Mayor Rudy Giuliani and six other defendants said in a court filing.

“Whether District Attorney Willis and her office are permitted to continue representing the State of Georgia in prosecuting the defendants in this action is of the utmost importance to this case, and ensuring the appellate courts have the opportunity to weigh in on these matters pre-trial is paramount,” they wrote.

The filing asks Fulton County Superior Court Judge Scott McAfee to grant a certificate that would allow his decision to be reviewed by the Georgia Court of Appeals.

Judge McAfee ruled on Friday that special prosecutor Nathan Wade had to leave the case or Ms Willis could not continue to pursue the charges.

Mr Wade later resigned, allowing Ms Willis to remain on the most sprawling of four criminal cases against the presumptive Republican nominee in the 2024 presidential election.

Judge McAfee did not find that Ms Willis’s relationship with Mr Wade amounted to a conflict of interest but said the allegations created an “appearance of impropriety” that infected the prosecution team.

Lawyers for Mr Trump and the other defendants who joined Monday’s filing said a failure to remove Ms Willis now could imperil any convictions and force a retrial if an appeals court later finds it was warranted.

“Neither the court nor the parties should run an unnecessary risk of having to go through that process more than once,” they wrote.

Ms Willis hired Mr Wade in 2021 to lead the team to investigate and ultimately prosecute Mr Trump and 18 others on charges that they illegally tried to overturn his narrow loss to Democrat Joe Biden in Georgia in 2020.

The case uses a statute normally associated with mobsters to accuse the former president, lawyers and other aides of a “criminal enterprise” to keep him in power.

Ms Willis and Mr Wade gave evidence at a hearing last month that they had engaged in a romantic relationship, but they rejected the idea that Ms Willis improperly benefited from it, as lawyers for Mr Trump and some of his co-defendants alleged.

Ms Willis and Mr Wade insisted they did not begin dating until after he became special prosecutor and the relationship ended in the summer of 2023. They both said that Ms Willis either paid for things herself or used cash to reimburse Mr Wade for travel expenses.

Judge McAfee wrote that there was insufficient evidence that Ms Willis had a personal stake in the prosecution. And he said he was unable to “conclusively establish by a preponderance of the evidence” whether Ms Willis and Mr Wade began dating before or after he was hired as special prosecutor.

“However, an odor of mendacity remains,” the judge wrote.

The judge also called a speech Ms Willis gave at a historic black church in Atlanta less than a week after the allegations of her relationship with Mr Wade surfaced “legally improper”.

Ms Willis complained in those remarks that people had questioned her decision to hire Mr Wade and questioned his qualifications, seeming to suggest the criticism arose from the fact that she and Mr Wade are black.

Monday’s filing cited the speech and argued an appellate court would likely find it and the appearance of impropriety Judge McAfee found sufficient to disqualify Ms Willis.