Explained: 13 key moments that shaped the trial of Derek Chauvin

These themes became clear almost immediately, in tearful testimony from bystander witnesses and criticism of Chauvin from experts called by the prosecution. In the final days of the trial, the defense brought the opposite account to the stand, giving the former police officer some support after more than two weeks of almost entirely critical testimony.

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The trial, and its verdict, have attracted more attention than almost any other criminal proceeding in decades, and as it moves into the final phase — closing arguments Monday, followed by jury deliberations and the verdict on Tuesday — these key moments illustrate some of the themes that are most important to jurors.

In the first week of the trial, many of the witnesses who were called by the prosecution had seen Floyd’s arrest in person. Their testimony gave jurors a clearer view of the final moments of Floyd’s life and demonstrated just how jarring seeing the arrest firsthand had been. Several witnesses cried as they recounted the arrest; some said that they felt guilty for not intervening and that they knew Floyd had been in grave danger. Their accounts set the tone for the rest of the trial and showed how widespread the impact of Floyd’s death had been.

Darnella Frazier was 17 when she took a video of the arrest that helped prompt a wave of protests across the country. Frazier was one of a handful of young witnesses who testified off camera. On May 25, she arrived at the Cup Foods convenience store with her 9-year-old cousin.

“It seemed like he knew it was over for him,” she said of Floyd. “He was terrified.”

Charles McMillian, another bystander witness, talked with Floyd as he was being pinned by Chauvin. McMillian told the jury that he had urged Floyd to get up and get in the police cruiser.

“Once the police get the cuffs on you, you can’t win,” he said during his testimony.

Floyd, held to the ground by Chauvin, replied that he couldn’t.

McMillian, 61, broke down in tears on the stand, and the court took a short break as he recovered. His testimony, perhaps more than anyone else’s, showed just how painful it was to see the arrest in person. Particularly traumatic for McMillian was the fact that Floyd had called out “Mama” in the few minutes before he lost consciousness.

This May 25, 2020, file image from a police body camera shows bystanders including Alyssa Funari, left filming, Charles McMillan, center left in light colored shorts, Christopher Martin center in gray, Donald Williams, center in black, Genevieve Hansen, fourth from right filming, and Darnella Frazier, third from right filming. (Minneapolis Police Department via AP, File)

Courteney Ross, who dated Floyd for nearly three years before his death, gave the jury and the public a rare glimpse into the life and personality of Floyd. Ross talked about their relationship, their first kiss, how Floyd loved to eat and how he helped her explore Minneapolis. Both sweet and tragic, her testimony humanized Floyd in a way that jurors had not heard up to that point. Ross also talked about a primary issue in the case: Floyd’s drug use.

The defense has argued that Floyd died largely from complications of drug use rather than as a result of being held down by Chauvin. Ross said the couple had struggled with opioid addiction. She said that their drug use began with legal prescriptions for chronic pain.

“We got addicted,” she said, “and we tried really hard to break that addiction many times.”

By the time paramedics arrived, Floyd had been unresponsive for several minutes, still pinned under Chauvin’s knee. Derek Smith, one of the paramedics who responded to the scene, testified that he looked for Floyd’s pulse almost as soon as he arrived but found none.

“In lay terms, I thought he was dead,” Smith said.

His testimony gave jurors a clearer understanding of what happened in the minutes after the arrest, and of the efforts made to save Floyd’s life on the way to the hospital. Despite his efforts, which included using a defibrillator and a machine that provides chest compressions, Smith could not revive Floyd, he said. The police officers who arrested Floyd provided no medical care at the scene, even after one officer failed to detect a pulse.

In a rare condemnation of an officer by an acting police chief, Chief Medaria Arradondo of the Minneapolis Police Department testified that Chauvin violated police policy when he knelt on Floyd for more than nine minutes.

“Once Mr. Floyd had stopped resisting, and certainly once he was in distress and trying to verbalize that, that should have stopped,” the chief said.

Arradondo said Chauvin also violated policy by not providing medical aid to Floyd once he became unresponsive.

Throughout the trial, Eric Nelson, the defense attorney for Chauvin, has suggested that the crowd of bystanders may have made it more difficult for Chauvin to render aid or to move Floyd from the prone position. Police Officer Nicole Mackenzie, who trains Minneapolis officers on providing medical care, conceded during cross-examination that bystanders can make it harder for officers to see signs of distress in people who are in custody.

Mackenzie’s testimony could lend support to the defense’s argument that other factors were at play and that jurors should view the situation in context. The crowd of about a dozen people yelled at the officers and urged Chauvin to move his knee, although they were otherwise peaceful and did not attempt to intervene.

People celebrate after the jury found Derek Chauvin guilty of murdering George Floyd, in Minneapolis on Tuesday, April 20, 2021. (The New York Times: Amr Alfiky)

Arguably the most important question in this case is what caused Floyd’s death. The prosecution has maintained that Floyd died from asphyxia, or the deprivation of oxygen, and has called several expert witnesses to support that notion. Dr. Martin Tobin, a pulmonologist and a world-renowned expert on breathing, agreed, saying that Floyd died from a lack of oxygen imposed by the restraint.

In his testimony, Tobin broke down the arrest in vivid detail, even identifying what he believed to be the exact moment that Floyd died.

Tobin said he saw no evidence of an overdose, striking a blow to the defense’s contention that drugs played a primary role in Floyd’s death. In nuanced testimony, Tobin counted Floyd’s breaths and said that he was breathing at a regular rate in the minutes before he died. Had he been suffering an overdose, Tobin said, the rate of breath should have slowed.

Although regular in interval, the breaths were not deep enough to sustain life, Tobin said. He was one of several expert witnesses who testified they saw no evidence of an overdose.

Dr. Bill Smock, a surgeon for the Louisville Metro Police Department, also testified that Floyd died from a lack of oxygen.

“He gradually succumbed to lower and lower levels of oxygen till it was gone and he died,” Smock said.

Although a toxicology report found fentanyl and methamphetamine in Floyd’s system, Smock said Floyd’s behavior did not correspond with that of a typical fentanyl overdose victim. Had he overdosed on fentanyl, Smock said, Floyd most likely would have slipped out of consciousness without a fight. Instead, Floyd yelled and begged for air.

Nelson, the attorney leading Chauvin’s defense, has argued throughout the trial that other factors, including drug use and an underlying heart condition, led to Floyd’s death. But witness after witness called by the prosecution disputed that claim, saying that they saw no evidence of a drug overdose and that Chauvin’s restraint of Floyd was potentially life-threatening.

One witness, called by the defense, said the opposite. Dr. David Fowler, the former chief medical examiner for the state of Maryland, said he saw no evidence that Chauvin’s knee hurt Floyd in any way. His testimony followed that of another expert witness for the defense, who testified that Chauvin was acting within the bounds of normal policing when he held Floyd in the prone position for 9 1/2 minutes.

Fowler and Barry Brodd, a use-of-force expert called by the defense, were the first and only witnesses to offer Chauvin such unequivocal support.

Both men faced tough cross-examination, though, and prosecuting attorneys scored several key points during their testimonies. Fowler admitted that Floyd should have been given medical attention and said that the sudden cardiac arrest that he believes killed Floyd could have been reversible.

The use-of-force expert called by the defense faced similar struggles during cross-examination. Brodd, a former police officer, at first said Chauvin’s restraint did not even qualify as a “use of force” but then conceded that, under the policies of the Minneapolis Police Department, it did. He also agreed when prosecutors asked whether the level of force should change depending on how much a suspect is resisting; Chauvin continued to hold his knee on top of Floyd for several minutes after he became unresponsive.

One of the most important questions in the trial was answered Thursday when Chauvin said he would invoke his Fifth Amendment right not to testify. Although his actions set off a national reckoning over the intersection of race and policing, the public has heard little from the former officer.