Three former Minneapolis police officers charged with violating George Floyd’s civil rights did nothing to intervene as fellow officer Derek Chauvin pinned the black man’s neck to the street, a prosecutor has told jurors.

“For second after second, minute after minute, these three CPR-trained defendants stood and knelt next to … Chauvin as he … killed George Floyd right in front of them,” prosecutor Samantha Trepel said as opening statements got under way at the officers’ federal trial in St Paul, Minnesota.

J Kueng, Thomas Lane and Tou Thao are broadly charged with depriving Mr Floyd of his civil rights while acting under government authority.

All three are charged with failing to provide Mr Floyd with medical care.

Thao and Kueng face an additional count of failing to stop Chauvin, who was convicted of murder and manslaughter in state court last year.

Defence lawyers planned to give opening statements later.

Legal experts say prosecutors must prove Kueng, Lane and Thao wilfully violated Mr Floyd’s constitutional rights, while defence lawyers are likely to blame Chauvin for Mr Floyd’s murder, which was video taped and triggered worldwide protests, violence and a re-examination of racism and policing.

Mr Floyd died on May 25 2020 after Chauvin pressed him to the ground with his knee on his neck for nine-and-a-half minutes while the 46-year-old was face down, handcuffed and gasping for air.

Kueng knelt on Mr Floyd’s back and Lane held down his legs.

Thao kept bystanders from intervening.

Lawyers for the Floyd family have said bystander video shows that the three officers “directly contributed to (Mr Floyd’s) death and failed to intervene to stop the senseless murder”.

Last week, 18 people were swiftly chosen for the jury; 12 will deliberate and six will be alternates.

Two of the jurors – one expected to deliberate and one alternate – appear to be of Asian descent.

The rest appear to be white.

The jurors include people from the Twin Cities area, the suburbs and southern Minnesota.

The court declined to provide demographic information.

Federal prosecutions of officers involved in on-duty killings are rare.

Prosecutors face a high legal standard to show that an officer wilfully deprived someone of their constitutional rights.

Essentially, prosecutors must prove that the officers knew what they were doing was wrong, but did it anyway.

The indictment charges Thao, who is Hmong American; Lane, who is white; and Kueng, who is black, with wilfully depriving Mr Floyd of the right to be free from an officer’s deliberate indifference to his medical needs.

The indictment says the three men saw Mr Floyd clearly needed medical care and failed to aid him.

Thao and Kueng are also charged with a second count alleging they wilfully violated Mr Floyd’s right to be free from unreasonable seizure by not stopping Chauvin as he knelt on Mr Floyd’s neck.

It is not clear why Lane is not mentioned in that count, but evidence shows he asked twice whether Mr Floyd should be rolled on his side.

Both counts allege the officers’ actions resulted in Mr Floyd’s death.

US District Judge Magnuson told jurors that the trial could last four weeks.

It is not known whether any of the three officers will give evidence.

It is also not clear whether Chauvin will give evidence, though many experts who spoke to the Associated Press believe he will not.

Lane, Kueng and Thao also face a separate state trial in June on charges they aided and abetted both murder and manslaughter.