The chief of the Minneapolis Police Department and the doctor who pronounced George Floyd dead both testified in the trial of former officer Derek Chauvin on Monday, providing key support for prosecutors’ arguments that Mr. Chauvin’s actions last May killed Mr. Floyd.
Here are some key takeaways from Day 7 of the trial.
A police use-of-force instructor faced questions about neck restraints.
Lt. Johnny Mercil, the second witness of the day, is a veteran of the Minneapolis Police Department, a practitioner of Brazilian jiu-jitsu and a use-of-force instructor who has trained hundreds of police officers.
His testimony focused on a crucial argument for the prosecution: that Derek Chauvin’s actions last May were not consistent with how officers have been taught to restrain people who are resisting arrest.
Steve Schleicher, a prosecutor, displayed a picture of Mr. Chauvin pinning George Floyd to the ground and asked, “Is this an M.P.D.-trained neck restraint?”
“No, sir,” Lieutenant Mercil responded.
The lieutenant, who is currently on medical leave from the Minneapolis Police Department, is the seventh member of the department to testify for the prosecution in Mr. Chauvin’s trial.
But Eric J. Nelson, a lawyer for Mr. Chauvin, countered with a line of questioning emphasizing the unpredictability of people who are being taken into custody, the possibility that they could stop resisting arrest and then suddenly become violent, and the challenge for police officers in assessing a situation as circumstances shift.
He suggested that Mr. Chauvin’s knee was not the cause of Mr. Floyd’s unconsciousness, and asked Lieutenant Mercil whether a restraint requires pressure on both sides of the neck for the person to go unconscious. “That is what we teach, yes,” he said.
Mr. Nelson repeatedly invoked the chaotic scene around Mr. Chauvin last May, asking Lieutenant Mercil whether bystanders yelling insults at an officer would “reasonably tend to rise alarm in an officer.” He agreed that they would.
Mr. Schleicher, the prosecutor, then asked: “And if they’re saying, ‘Get off him, you’re killing him,’ should the officer also take that into account and consider whether their actions need to be reassessed?”
“Potentially, sir, yes,” Lieutenant Mercil said.
Minneapolis police training procedures and policies remained in focus.
Lawyers for both the prosecution and the defense continued to argue on Tuesday over whether Mr. Chauvin violated police policy when he knelt on Mr. Floyd, asking a range of questions to the day’s first witness, a crisis intervention coordinator with the Minneapolis Police Department.
Prosecutors called the coordinator, Sgt. Ker Yang, 49, to the stand and walked through the various decisions that officers are expected to make while on the job. Steve Schleicher, a prosecutor, emphasized in his questions that the police are supposed to constantly re-evaluate a situation and act accordingly, to which Sergeant Yang agreed.
“When we talk about fast-evolving situations, I know that they do exist, they do happen,” Sergeant Yang testified. But in many situations, he added, “We have the time to slow things down and re-evaluate and reassess.”
His comments echoed those of Chief Medaria Arradondo, who on Monday testified that while Mr. Chauvin’s initial efforts to restrain Mr. Floyd may have been reasonable, he had violated policy by continuing to kneel on Mr. Floyd for more than nine minutes.
Mr. Schleicher noted on Tuesday that Mr. Chauvin had participated in a 40-hour crisis intervention training course in 2016.
Eric J. Nelson, Mr. Chauvin’s lawyer, pressed his argument that bystanders at the scene of an arrest can have a large effect on how an officer acts, and that an officer can “look bad” even while using force that is lawful. He also emphasized that officers are not supposed to remain solely focused on someone they are arresting, but are also supposed to consider other parts of their surroundings.
“It’s not just one small thing that you’re focused only on the subject that you’re arresting,” Mr. Nelson said. “You’re taking in a lot of information and processing it all kind of simultaneously through this critical decision-making model.” Sergeant Yang agreed.
A friend of George Floyd’s who was with him when he was arrested is trying to avoid testifying.
Morries Lester Hall, a friend of Mr. Floyd’s who was in a car with him moments before the police pulled Mr. Floyd out of the car and pinned him to the ground, is hoping to avoid testifying in the murder trial.
At a hearing on Tuesday morning over whether Mr. Hall must testify, his lawyer said that testifying about any of his actions on May 25 had the potential to incriminate him, and that Mr. Hall planned to invoke his Fifth Amendment right against self-incrimination. Mr. Hall, who is currently in jail on charges unrelated to Mr. Floyd’s death, appeared in court by video conference, though he spoke only to spell his name and confirm that he had conferred with his lawyer.
Judge Peter A. Cahill, who is overseeing the trial of Mr. Chauvin, did not rule on whether Mr. Hall must testify, but he ordered Mr. Chauvin’s lawyer to draft a list of questions by Thursday that Mr. Hall might be able to answer without incriminating himself. Videos from the scene show that Mr. Hall was sitting in the passenger seat of a car when the police initially confronted Mr. Floyd, shortly before he was pinned to the ground and died.
Adrienne Cousins, Mr. Hall’s lawyer, said that both prosecutors and Mr. Chauvin’s lawyer had subpoenaed Mr. Hall, though Mr. Nelson seemed more interested in calling him to the stand. Mr. Nelson said in court that he wanted to ask Mr. Hall a range of questions, including about whether he had given Mr. Floyd drugs, about the fake $20 bill that a convenience store clerk said Mr. Floyd used, and about why Mr. Hall left Minnesota after Mr. Floyd had died.
Ms. Cousins said that all of those questions could incriminate her client, and Judge Cahill largely seemed to agree. But the judge said there may be a narrow range of questions — possibly on how Mr. Floyd appeared to be acting in the car before the police arrived — that Mr. Hall might be able to answer without incriminating himself. Ms. Cousins strenuously disagreed, saying that even acknowledging that Mr. Hall was in the car with Mr. Floyd on May 25 could be used against him if he were to be charged with a crime based on his actions that day.
For their part, prosecutors seemed most worried about the prospect that Mr. Hall would take the stand and invoke his Fifth Amendment right in front of the jury, perhaps making them further question Mr. Floyd’s actions that day or making them concerned about what is being withheld.