Factbox-Key moments from seventh day of witness testimony at Chauvin trial

(Reuters) - The jury in the trial of former Minneapolis police officer Derek Chauvin, charged with the murder of George Floyd last May, heard testimony on Tuesday from members of the police department who trained him in safely using force and providing first aid.

Chauvin, who is white, pressed his knee into the neck of Floyd, a 46-year-old Black man in handcuffs, for about nine minutes on May 25, 2020, a scene that ignited global protests against police brutality.

The county medical examiner has ruled Floyd's death a homicide at the hands of the police. Chauvin's lawyers argue Floyd's death was a drug overdose, though prosecutors have said medical evidence would contradict that.

Here are some of the important moments from the seventh day of testimony on Tuesday:

SERGEANT KER YANG, CRISIS INTERVENTION TRAINING COORDINATOR

Sergeant Ker Yang, a crisis intervention training coordinator for the Minneapolis Police Department, testified that Chauvin completed 40 hours of training on dealing with suspects going through a crisis.

Yang said police are trained to use principles such as respect and trust in crisis intervention situations, and how to spot and interact with suspects going through a crisis.

LIEUTENANT JOHNNY MERCIL, USE-OF-FORCE INSTRUCTOR

Mercil testified that he trains Minneapolis police officers in how to use a proportional amount of force and properly use neck restraints, handcuffs and straps.

"If you can use the least amount of force to meet your objectives, it is safer and better," Mercil testified. "It's very important to be careful."

Mercil testified that a neck restraint designed to render a suspect unconscious is authorized only when the suspect is actively and aggressively resisting.

On cross-examination, Mercil agreed with Chauvin's attorney Eric Nelson when asked whether officers must protect themselves when arresting unruly subjects during evolving situations.

Nelson questioned Mercil about safety precautions officers need to take when using neck restraints and body weight to restrain individuals.

"We tell them to stay away from the neck when possible," Mercil told jurors.

The city's police chief testified on Monday that Chauvin violated department rules and its ethics code while arresting Floyd.

NICOLE MACKENZIE, MEDICAL SUPPORT COORDINATOR

Officer Nicole Mackenzie, who trained officers including Chauvin in how and when to perform CPR, told the jury that if officers cannot find a pulse on a subject, they are taught to immediately begin CPR. In Floyd's arrest, Chauvin did not perform CPR.

"Just because they're speaking doesn't mean they're breathing adequately," Mackenzie testified.

Questioned by the defense, Mackenzie said that officers must take into account the impact drugs have on a subject's behavior and should consider the safety of their surroundings when deciding whether to administer first aid.

LOS ANGELES POLICE DEPARTMENT SERGEANT JODY STIGER, USE-OF-FORCE EXPERT

Stiger, who has reviewed 2,500 use-of-force cases, took the stand as a witness for the prosecution. Stiger testified that he reviewed Chauvin's use of force toward Floyd and found it to be "excessive."

Stiger said that the officers could have talked to Floyd instead of trying to force him into the back of the police squad car, but agreed that it was not unreasonable.

During Stiger's testimony, Cahill abruptly adjourned the trial for the day.

HEARING ON REQUEST TO QUASH SUBPOENA

Before the jury was brought into the courtroom in the morning, Hennepin County District Judge Peter Cahill heard arguments on whether to quash a defense subpoena requiring a friend of Floyd's testify.

The friend, Morries Hall, was in the car with Floyd when police arrived before the deadly arrest, and Chauvin's lawyer told the jury that he would testify that he saw Floyd take pills and fall into a deep sleep. Hall has said that he would invoke his constitutional right against self-incrimination if he had to appear on the witness stand.

Nelson told Cahill he planned to ask Hall whether he gave Floyd any controlled substances and why Hall left Minnesota immediately after Floyd's death. Floyd's girlfriend testified last week that she and Floyd struggled with opioid addiction, and that she thought Hall sometimes illegally sold pills to Floyd.

A public defender, Adrienne Cousins, represented Hall in court, saying that he had not been offered immunity and was at risk of incriminating himself in third-degree murder, a charge Minnesota sometimes uses to prosecute a drug dealer after a customer fatally overdoses.

The judge gave Nelson until Thursday to draft potential questions before deciding whether Hall must testify.