SAINT PAUL, MINNESOTA (AFP) - Former Minneapolis policeman Derek Chauvin is serving 22 years in prison for the murder of Mr George Floyd, a 46-year-old African-American.
Now the other three ex-police officers on the scene are going on trial for their actions that day - or rather their failure to take action.
A jury - 12 jurors and six alternates - was selected on Thursday (Jan 20) in the federal trial of Tou Thao, J. Alexander Kueng and Thomas Lane, accused of violating Mr Floyd's civil rights.
Chauvin was convicted of murder in a state trial and pleaded guilty last month to federal charges of using excessive force during Mr Floyd's May 25, 2020 arrest for allegedly using a fake US$20 (S$26.93) to buy a pack of cigarettes.
Mr Floyd's death, which was filmed by a bystander on a mobile phone, set off months of protests in the United States against racial injustice and police brutality.
Chauvin kept his knee on the handcuffed Mr Floyd's neck for nearly 10 minutes, while Kueng was on his back and Lane held his legs.
Thao kept back bystanders who were pleading with Chauvin to get off the neck of a visibly distressed Mr Floyd, who eventually passed out and died.
Chauvin was an 18-year veteran of the Minneapolis police force; Thao had served for eight years while Kueng and Lane were new recruits, having joined the department in December 2019.
Thao, Kueng and Lane are to face Minnesota state charges in connection with Mr Floyd's death in a trial which is now scheduled to begin on June 13 after repeated delays.
But in a sign of the importance of the case, federal prosecutors also charged the officers with violating Mr Floyd's constitutional rights.
The indictment charges Thao, Kueng and Lane with showing "deliberate indifference to (Floyd's) serious medical needs".
Thao and Kueng also "wilfully failed to intervene" to stop Chauvin's "use of unreasonable force" against Mr Floyd, according to the indictment.
Lane does not face the second charge. Video of the arrest shows that on two occasions, Lane suggested that Mr Floyd be rolled over on his side.
The federal trial is being held in a heavily guarded courtroom in Saint Paul, the sister city to Minneapolis.
All three men have pleaded not guilty.
Lawyers for Kueng and Lane are expected to argue during the trial that the men were not in a position to challenge the authority of Chauvin, the senior officer on the scene.
Thao's attorney is expected to claim that his client's attention was focused on keeping back the onlookers, and he was not aware of Mr Floyd's condition.
Mr Ben Crump, a lawyer for the Floyd family, described the trial as "another milestone in the long, slow journey to justice for George Floyd and his family".
He said: "We fully expect them to be held accountable for their roles in willingly violating the civil rights of George Floyd, leading to his tragic death."
US District Judge Paul Magnuson has set aside two days for jury selection.
Opening arguments in the trial, which is expected to last at least two weeks, could start on Monday.
Unlike Chauvin's state trial, the federal trial is not being televised.