A judge in the Georgia election interference case against former President Donald J. Trump is scheduled to hear final arguments on Friday on a motion to disqualify the prosecutor who brought the case, Fani T. Willis, on the ground that a romantic relationship she had with a subordinate created a conflict of interest.

The presiding judge, Scott McAfee of Fulton County Superior Court, is not likely to rule on the matter on Friday. Rather, the hearing, which is scheduled to start at 1 p.m., will allow lawyers from the two sides to sum up their arguments over a salacious subplot to the election case — one that has already caused significant embarrassment and turmoil for Ms. Willis, the Fulton County district attorney. Details of her personal life have been spilled out in the Atlanta courthouse where she had hoped to put Mr. Trump and 14 co-defendants on trial as soon as this summer.

The stakes are high: If Ms. Willis is disqualified from the case, her entire office would be, too, and the case would probably be turned over to a district attorney from another jurisdiction. The new prosecutor could choose to continue the case as planned, modify the charges or drop them.

Disqualification would reduce the chances that a trial would begin before the November presidential election, in which Mr. Trump is expected to be the Republican nominee.

The relationship between Ms. Willis and Nathan Wade, an Atlanta-area lawyer she hired in November 2021 to manage the prosecution team, first came to light in January, in a motion filed by a lawyer for one of Mr. Trump’s co-defendants.