The white former Minneapolis police officer convicted last month of the murder of the black man George Floyd has requested a new trial.
Derek Chauvin’s legal team have filed court documents alleging misconduct by both prosecutors and jurors.
Chauvin, who was captured on video kneeling on Mr Floyd’s neck for more than nine minutes, was found guilty of murder and manslaughter.
His lawyer says his client was deprived of a fair trial.
The rare verdict against a police officer was considered a milestone in the racial history of the US and was widely applauded by Americans. Chauvin faces up to 40 years in prison.
He will be sentenced next month.
What is Chauvin’s legal team arguing?
US media report that the request for a new trial was expected and is a common move following a conviction.
The New York Times quoted experts as saying it was unlikely that the jury’s decision would be overturned because of the evidence in the case.
In court documents Eric Nelson argues that the process was not impartial because of pre-trial publicity.
He writes that it was “so pervasive and so prejudicial” before and during the trial, that it amounted to a “structural defect in the proceedings”.
The motion also alleges that errors were made by the judge and that there was prosecutorial misconduct and witness intimidation.
What is the controversy about the juror?
Supporters of Chauvin have pointed to juror Brandon Mitchell, who was pictured last August at an event in Washington held on the 57th anniversary of the civil rights movement’s historic March on Washington.
The event included a Get Your Knee Off Our Necks protest at which speakers including Martin Luther King’s son demanded racial equality. Mr Mitchell was pictured wearing a T-shirt bearing the slogan “Get your knee off our necks” and “BLM”, referring to the Black Lives Matter movement.
Jurors in the Chauvin case were asked before the trial whether they or people they knew well had “participated in protests about police use of force or police brutality”.
Mr Mitchell – the only juror in the trial to give media interviews – says he answered no to that question.
He told the Minneapolis Star Tribune that he had attended the event to commemorate the civil rights movement and had not seen it as an anti-police brutality protest.
“The opportunity to be around thousands and thousands of black people, I just thought it was a good opportunity to be a part of something,” he said.
Before the trial, during questioning by Chauvin’s defence team, Mr Mitchell said that he saw Black Lives Matter as a statement that he supported.