WASHINGTON - The police officer who killed African American George Floyd in 2020 asked an appeals court Wednesday to overturn his murder conviction, arguing that the extreme media attention and potential for riots had deprived him of a “fair” trial.

Derek Chauvin, 46, was convicted of murder in Minnesota after a closely watched trial in 2021 and sentenced to 22 and a half years in prison.

His lawyer William Mohrman pleaded with a panel of judges Wednesday to overturn the trial, in part because the hearings had not been moved despite threats of violence around the courthouse.

“The primary issue on this appeal is whether a criminal defendant can get a fair trial... in a courthouse that is surrounded by concrete block, barbed wire, two armoured personnel carriers and a squad of National Guard troops, all of which are there... in the event that the jury acquits the defendant,” Mr Mohrman said.

Whatever happens during the appeal, Chauvin will remain in prison. He pleaded guilty to violating Mr Floyd’s civil rights before a federal judge in 2022 and received a 21-year prison sentence.

Three other police officers, who remained passive during Mr Floyd’s death, received sentences ranging from two and a half to three and a half years in prison.

On May 25, 2020, Chauvin, a white 19-year veteran of the Minneapolis police force, knelt on the neck of the African American man in his forties for nearly ten minutes, indifferent to his cries and to the warnings of distraught passersby.

The scene, filmed and posted online, triggered mass demonstrations against racism and police violence in the United States and beyond.

During the local court trial, his lawyer pleaded that Mr Floyd died of an overdose, combined with health problems, and had assured that Chauvin had made a justified use of force.

Today, Chauvin is asking the court to throw out his conviction or at least his sentence, partly because the trial was held in the Twin Cities of Minneapolis and St. Paul, which were still on edge less than a year after the tragedy.

During jury selection, all the candidates “expressed concerns for their safety” and fear that their city would flare up again if they acquitted Chauvin, Mr Mohrman said.

“You can’t hold a trial in a community where the jurors are looking at the possibility of a riot in the event that the jurors would acquit the defendant,” he added.

“This case could not be tried in Minneapolis because of the pre-trial publicity which was pervasive,” he said.

In a written filing, Mr Mohrman criticised the news media for having “idealised George Floyd and demonised Derek Chauvin.”

Mr Neal Katyal, the former acting US solicitor-general who now is a Minnesota special prosecutor, called it “one of the most transparent and thorough trials in our nation’s history.”

“The court and parties painstakingly selected jury over two weeks, 44 witnesses testified, jurors watched video footage and heard from bystanders,” Mr Katyal said.

“Even if Chauvin could identify some minor faults, any error is harmless. The evidence of Chauvin’s guilt was captured on video for the world to see,” he added.

Echoing some of Mr Mohrman’s arguments, Mr Katyal said that the omission of a juror who did not reveal that he had attended an anti-racist march in Washington was not a lie that would disqualify the trial.

This man “was very clear about his views on police brutality” and the defence made a conscious decision to keep him on the jury, he noted.

Judges have 90 days to hand down a ruling. AFP