Former Minneapolis police officer Derek Chauvin has been sentenced to 22.5 years in jail for murdering George Floyd in May 2020 after a trial that was widely seen as a watershed moment in the history of US policing.

A jury found Chauvin, 45, guilty on April 20 of unintentional second-degree murder, third-degree murder and second-degree manslaughter.

Chauvin, who appeared in court for the sentencing, had asked the judge through his lawyer to sentence him to probation, writing that the murder of Floyd was “best described as an error made in good faith”.

“I want to give my condolences to the Floyd family,” Chauvin said, during his sentencing appearance.

“There’s going to be some other information in the future that would be of interest and I hope things will give you some peace of mind.”

The prosecution had asked for 30 years which is double the upper limit indicated in sentencing guidelines for a first-time offender.

Floyd’s seven-year-old daughter Gianna appeared in a video recording played for Hennepin County District Judge Peter Cahill.

“I ask about him all the time,” she said in the video as Chauvin sat before the judge dressed in a grey suit and tie, a blue medical mask covering his nose and mouth.

“My daddy always used to help me brush my teeth.”

Asked what she would say to him if she could see him again, she said: “It would be I miss you and I love you.”

Supporters gather next to the spot where George Floyd was killed, during the sentencing hearing. Photo: AAP

George Floyd’s sister Bridgett released a statement welcoming the sentence but she said the fight was not over.

“The sentence handed down today to the Minneapolis police officer who killed my brother George Floyd shows that matters of police brutality are finally being taken seriously,” the statement said.

“However, we have a long way to go and many changes to make before Black and Brown people finally feel like they are being treated fairly and humanely by law enforcement in this country.”

Chauvin’s lawyer has argued that he was deprived of a fair trial because of prosecutorial and jury misconduct and errors of law at trial.

Judge Cahill denied Chauvin’s request for a new trial in an order on Friday morning.

Video of Chauvin, who is white, kneeling on the neck of Floyd, a 46-year-old black man in handcuffs, for more than nine minutes sparked outrage around the world and the largest protest movement seen in the United States in decades.

In a sentencing memorandum, prosecutors from the Minnesota attorney general’s office wrote that Chauvin’s crime “shocked the conscience of the nation”.

In a six-page ruling last month, Judge Cahill found that prosecutors had shown there were four aggravating factors that would allow him to hand down a longer prison term than sentencing guidelines would dictate.

The judge agreed that Chauvin abused his position of trust and authority; that he treated Floyd with particular cruelty; that he committed the crime as part of a group with three other officers; and that he committed the murder in front of children.

A gathering in George Floyd Square, Minneapolis. Photo: Getty

Chauvin was helping arrest Floyd on suspicion of using a fake $US20 bank note.

Chauvin, who chose not to testify at his trial, has a right to address the judge before he is sentenced.

Mary Moriarty, Hennepin County’s former chief public defender, said in an interview that the judge may take note that Chauvin did not express remorse in the sentencing memorandum submitted this month by his lawyer.

“I think what Cahill would have been looking for from Chauvin or through his defence counsel is some responsibility for his actions or some empathy for George Floyd,” she said.

Chauvin has been held at the state’s maximum security prison in Oak Park Heights since his conviction.

In Minnesota, convicted people with good behaviour spend two-thirds of their sentence in prison and the final third on supervised release.

-with AAP