The trial of Derek Chauvin continued Tuesday with an array of police experts who testified that Chauvin failed to follow his training, from use of force to CPR, during his arrest of George Floyd. The defense continued to underscore the role the crowd of bystanders had during the incident, arguing that they adversely impacted Chauvin’s decision process and responses during a fluid situation.

Several experts said with certainty that Chauvin’s neck restraint of Floyd was against guidance. “We tell officers to stay away from the neck when possible,” said Minneapolis Police Lt. Johnny Mercil, the use-of-force coordinator for the department. He called the restraint unauthorized and described it as “active aggression.”

Officer Nicole Mackenzie, the medical support coordinator for MPD, testified that officers like Chauvin who are trained in CPR learn that a subject’s ability to talk does not always mean they’re breathing properly. She also acknowledged under a line of questioning by defense lawyer Eric J. Nelson that distractions, like those from a surrounding crowd, can make it difficult to focus on lifesaving measures. The defense signaled it would bring her back to the stand when it starts its portion of the case.

Here’s what to know:

  • Mercil testified that suspects should be put in recovery position “as soon as possible” once they are prone to allow them to breathe.
  • Los Angeles Police Sgt. Jody Stiger, the prosecution’s use-of-force expert, testified that the force Chauvin exerted on Floyd was “excessive.”
  • Nelson argued that Chauvin did not administer a traditional chokehold on Floyd. He added that the officer had his knee on Floyd’s shoulder when paramedics arrived.
  • In cross-examination, Chauvin’s defense team repeatedly brought up the medical training for police surrounding excited delirium, which was previously cited by Nelson as one reason for Floyd’s death.
  • During the cross-examination of Minneapolis Police Sgt. Ker Yang, the department’s crisis training coordinator, Nelson said that the bystanders who yelled at the officers while they detained Floyd could have affected their crisis training.
  • In a motion hearing Tuesday, attorneys for Morries Hall argued that any testimony from the man with George Floyd inside his car before his death could potentially self-incriminate him on a murder charge in a possible, separate trial. Judge Peter Cahill offered a “narrow” option for Hall to provide testimony that will be reexamined later this week.