Mr Arradondo is one of several top officers in the Minneapolis police department to openly condemn Chauvin's actions to the court.

In this image from video, witness Minneapolis Police Chief Medaria Arradondo testifies as Hennepin County Judge Peter Cahill presides Monday, April 5, 2021, in the trial of former Minneapolis police Officer Derek Chauvin at the Hennepin County Courthouse in Minneapolis.

Prosecutors are seeking to prove that Mr Chauvin's actions violated his training and have focused their questions on police guidelines and strategies taught to help officers de-escalate situations.

Chauvin has pleaded not guilty to murder and manslaughter charges for Floyd's arrest on suspicion that Floyd had used a fake $20 bill to buy cigarettes at a store.

As jurors watched in rapt attention and scribbled notes, Arradondo testified not only that Chauvin, a 19-year veteran of the force, should have let Floyd up sooner, but that the pressure on Floyd's neck did not appear to be light to moderate, as called for under the department's neck-restraint policy; that Chauvin failed in his duty to render first aid before the ambulance arrived; and that he violated policy requiring officers to de-escalate tense situations with no or minimal force if they can.

He also said officers were taught that restraint was considered force and that they must use the least force required because "it's safer and better for everybody involved".

The harrowing footage of Floyd's arrest touched off protests against racial injustice and police brutality in the United States and around the world. Chauvin is charged in the May 25, 2020 death of George Floyd.

Prosecutor Steve Schleicher noted that while some people may become more unsafe under the influence of drugs or alcohol, some may actually be "more vulnerable".

A sergeant has admitted officers could have ended their restraint against George Floyd earlier than they did.

Records also show that Chauvin took in-service training in the use of force in October 2018.

Before he was pinned to the ground, a frantic Floyd struggled with police who were trying to put him in a squad vehicle, saying he was claustrophobic. He repeatedly said he was claustrophobic.

The judge said he would rule later on Hall's request not to testify.

"When we talk about fast-evolving situations. a lot of the time we have the time to slow things down and reevaluate and reassess and go through this model", Yang said.

Mr Chauvin's lawyer Eric Nelson has fought against that notion by emphasising that officers have to consider different factors while using force, such as potential threats from a nearby crowd.

Prosecutors have suggested that asphyxiation was the cause of Mr Floyd's death - contrasting with the ruling of the medical examiner who said Mr Floyd died of "cardiopulmonary arrest", which means a person's heart and lungs have stopped.

Mr Nelson also questioned whether Chauvin's knee was on Mr Floyd's neck, playing a few seconds of bystander video side-by-side with footage from an officer's body camera that Mr Arradondo agreed appeared to show Chauvin's knee on Mr Floyd's shoulder blade.

Sgt. Ker Yang, the Minneapolis police official in charge of crisis intervention training, and use-of-force instructor Lt. Johnny Mercil became the latest department members to testify as part of an effort by prosecutors to demolish the argument that Chauvin was doing what he was trained to do when he put his knee on George Floyd's neck last May.

Hall's lawyer said "there's an allegation here that Mr Floyd ingested a controlled substance as police were removing him from the vehicle". In June, he called Floyd's death a "murder" in response to an inquiry from the Minneapolis Star Tribune.

"We were taught about positional asphyxia all the way back to my academy", Blackwell said, adding that her time with the department overlaps with the length of time Chauvin has also been there.