A judge will rule within two weeks whether a Georgia district attorney who is prosecuting Donald Trump for alleged election meddling should be thrown off the case.
The central question is whether a romantic relationship between Fulton County District Attorney Fani Willis and the special prosecutor she hired, Nathan Wade, compromises the integrity of the case.
The two have acknowledged they had a romantic relationship, but insist the affair only began after Ms Willis hired Mr Wade to the case and deny they violated conflict of interest laws or misused funds.
The first female district attorney in Fulton County, Ms Willis charged Mr Trump and 18 co-defendants last year with conspiring to overturn the former president's 2020 election loss to Joe Biden in Georgia.
What's the latest?
Judge Scott McAfee, who is overseeing the Trump case, heard closing arguments on Friday to weigh whether the Willis-Wade relationship has, essentially, tainted the case.
Judge McAfee decided not to rule on the issue on Friday, saying a decision would come within two weeks.
At an evidentiary hearing this week, Mr Wade's former divorce lawyer was asked about texts he had sent to another attorney, in which he said Mr Wade and Ms Willis' relationship "absolutely" started before she hired him, and that the pair were "arrogant".
But during evasive testimony, the divorce lawyer, Terrence Bradley, cited attorney-client privilege and said he did not know or could not remember when Ms Willis and Mr Wade's affair began.
Last week, Mr Trump's legal team said in a court filing that phone data shows the pair exchanged more than 2,000 calls and nearly 12,000 interactions such as texts in the year before they say their relationship began. Ms Willis' office said the records were not relevant.
What are the allegations against Fani Willis?
In early January, one of Mr Trump's co-defendants, Michael Roman, filed a motion accusing Ms Willis of engaging in an "improper, clandestine personal relationship" with Mr Wade.
His attorneys filed subpoenas requiring them to appear at an evidentiary hearing on 15 February to be grilled about their romantic relationship. The legal papers cited records from Mr Wade's divorce proceedings.
Ms Willis asked the judge to scrap the hearings, but he declined to do so.
Mr Roman was an operations director on Mr Trump's 2020 presidential campaign and is seeking to have the charges against him dismissed.
He is accused of helping put forward a slate of fake pro-Trump electors (officials who certify election results) in Georgia and other battleground states.
Ms Willis has also been subpoenaed separately by the US House of Representatives' judiciary committee over allegations that she fired a whistleblower who tried to stop a campaign aide from misusing federal funds.
How have Fani Willis and Nathan Wade responded?
During her combative testimony last month, Ms Willis acknowledged a romantic relationship with Mr Wade, but argued that allegations of impropriety were unfounded and had no bearing on the election interference case.
She also denied testimony by her former friend, Robin Yeartie, that Ms Willis' affair with Mr Wade began before he joined the Trump case.
Ms Yeartie told the court she saw the pair hugging and kissing years before the case, and had "no doubt" the relationship started in 2019.
On the witness stand, Ms Willis insisted she and Mr Wade split the cost of their holidays together, which included two cruises to the Bahamas, and trips to Napa Valley, California, and Caribbean resorts in Aruba and Belize.
Mr Wade denied that he shared his compensation for working on the case with Ms Willis, adding that he never cohabitated, shared household expenses, or held a joint account with Ms Willis.
Ms Willis said in January that her critics were playing "the race card".
In an emotional speech at a church's Martin Luther King Jr Day celebration, she said she appointed three prosecutors but "they only attacked one", adding that the other two outside lawyers were white.
A lawyer for Mr Roman denies race was a factor in his accusations.
How does this affect Donald Trump?
Mr Trump has seized on the allegations.
He said on his social network, Truth Social, that the "lovebirds" were targeting him "in order to ENRICH themselves, and to live the Lifestyle of the Rich and Famous".
Mr Trump joined his co-defendant's motion to disqualify Ms Willis, arguing she violated state bar rules by claiming racism was motivating the effort to oust her.
Could the Georgia case collapse?
The challenge could set back the proceedings, but there is so far no indication the case itself will collapse.
Anthony Michael Kreis, a professor at Georgia State University College of Law, told the BBC: "A disqualification poses a real danger to the work done by the Fulton County DA's Office."
He said the legal threshold to remove her over a conflict of interest would be high. But if the defendants persuade a judge to disqualify Ms Willis, her entire office would be off the case.
Another office would have to be appointed, Prof Kreis explained. In that scenario, it is possible the trials would proceed as planned.
Or the new prosecutor could "make light plea deals, or even give up on the endeavour entirely", said Prof Kreis.
Who is Nathan Wade?
Once a municipal court judge, Mr Wade is a trial attorney who has "decades of experience helping clients facing divorce, separation, and child-custody issues", according to his firm's website.
In her speech at the church, Ms Willis hailed him as a "great friend and a great lawyer", and a legal "superstar" with "impeccable credentials".
But his website and career show little experience with complex criminal cases like Mr Trump's.
Still, Mr Wade was a "super competent judge" who was "timely, efficient with the docket and respectful", Holly Waltman, a criminal defence lawyer who knows him, told the BBC's US partner CBS News.