The video of George Floyd gasping for breath was essentially Exhibit A as the former Minneapolis police officer who pressed his knee on the black man's neck went on trial on Monday charged with murder and manslaughter.
Prosecutor Jerry Blackwell showed the jurors the footage during opening statements after telling them that the number to remember was nine minutes, 29 seconds – the amount of time Derek Chauvin had the man pinned to the pavement last May.
The white officer “didn’t let up” even after a handcuffed Floyd said 27 times that he couldn’t breathe and went limp, Mr Blackwell said.
The event triggered worldwide protests, scattered violence and national soul-searching over racial justice.
“He [Chauvin] put his knees upon his neck and his back, grinding and crushing him, until the very breath – no, ladies and gentlemen – until the very life was squeezed out of him,” the prosecutor said.
Mr Chauvin's lawyer Eric Nelson countered by saying, "Derek Chauvin did exactly what he had been trained to do over his 19-year career."
Floyd was resisting arrest, and Mr Chauvin arrived to assist other officers who were struggling to force him into a squad car as the crowd around them grew larger and more hostile, Mr Nelson said.
He also disputed the claim that Mr Chauvin was responsible for Floyd's death.
The 46-year-old had none of the telltale signs of asphyxiation, and had fentanyl and methamphetamine in his system, Mr Nelson said. He said Floyd's drug use, combined with his heart disease and high blood pressure, as well as the adrenalin flowing through his body caused his death from a heart rhythm disturbance.
“There is no political or social cause in this courtroom,” Mr Nelson said. “But the evidence is far greater than nine minutes and 29 seconds.”
The medical examiner’s post-mortem examination report noted fentanyl and methamphetamine in Floyd’s system but listed his cause of death as “cardiopulmonary arrest, complicating law enforcement subdual, restraint and neck compression”.
Mr Chauvin, 45, is charged with unintentional second-degree murder, third-degree murder and manslaughter. The most serious charge, the second-degree murder, carries up to 40 years in prison. The case is the first trial ever televised in Minnesota.
The first witness was Minneapolis police dispatcher Jena Scurry, who testified that she saw part of Floyd’s arrest unfolding via a city surveillance camera and was so disturbed that she called a duty sergeant.
Ms Scurry said she grew concerned because the officers hadn’t moved after several minutes.
“You can call me a snitch if you want to,” Ms Scurry said in her call to the sergeant, which was played in court.
She said she wouldn’t normally call the sergeant about the use of force because it was beyond the scope of her duties, but “my instincts were telling me that something is wrong".
The video played during the opening statements was posted to Facebook by a bystander who witnessed Floyd being arrested after he was accused of trying to pass a counterfeit $20 bill at a convenience store. The footage caused revulsion across the US and beyond.
It prompted calls for the country to confront racism and police brutality. Confederate statues and other symbols were pulled down around the US, and activists demanded that police department budgets be cut or overhauled.
US President Joe Biden will closely monitor developments in the trial of the police officer, White House Press Sectretary Jen Psaki said Monday.
"He certainly will be watching closely, as Americans across the country will be watching," Ms Psaki said.
"At the time of George Floyd's death, he talked about this as being an event that really opened up a wound in the American public."
Jurors watched intently as the video played on several screens, with one drawing a sharp breath as Floyd said he couldn't breathe. Mr Chauvin sat calmly during the proceedings and took notes, looking up at the video periodically.
“My stomach hurts. My neck hurts. Everything hurts,” Floyd says in the video. “I can’t breathe, officer.”
Onlookers repeatedly shout at the officer to get off of Floyd, saying he is not moving, breathing or resisting. One woman, identifying herself as a city fire department employee, shouts at Mr Chauvin to check Floyd’s pulse.
The prosecutor said Mr Chauvin used excessive force against someone who was handcuffed and not resisting, and the case was “not about split-second decision-making” by a police officer.
Mr Blackwell said the fire department employee who wanted to administer aid was warned off by Mr Chauvin, who pointed Mace at her.
"She wanted to check on his pulse, check on Mr Floyd's well-being," Mr Blackwell said. "She did her best to intervene. When she approached Mr Chauvin …. Mr Chauvin reached for his mace and pointed it in her direction. She couldn't help."
The chronology differs from the initial account submitted last May by prosecutors, who said Mr Chauvin held his knee on Floyd’s neck for eight minutes, 46 seconds. The time soon became a rallying cry in the case, but it was revised during the investigation.
Fourteen people in the jury box are hearing the case – eight of them white, six of them black or multiracial, according to the court. Two will be alternates, though the judge hasn’t said which ones will deliberate the case.
About a dozen people chanted and carried signs outside the court as Floyd family lawyer Ben Crump, the Reverend Al Sharpton and members of the Floyd family went inside.
George Floyd's family kneels before Derek Chauvin's trial starts
Mr Crump said the trial would be a test of “whether America is going to live up to the Declaration of Independence”, and blasted the idea that it would be a tough test for jurors.
“We know that if George Floyd was a white American citizen, and he suffered this painful, torturous death with a police officer’s knee on his neck, nobody – nobody – would be saying this is a hard case,” he said.
The court in central Minneapolis has been fortified with concrete barriers, fences, and barbed and razor wire. City and state leaders are determined to prevent a repeat of the riots that followed Floyd's death, with National Guard troops already mobilised.
Mr Chauvin’s trial is being live-streamed, a first in Minnesota, by order of the judge and over the objections of the prosecution.
Judge Peter Cahill ordered that cameras be allowed largely because of the pandemic and the required social distancing that meant there would be almost no room for spectators in the court.
The key questions will be whether Mr Chauvin caused Floyd’s death and whether his actions were reasonable.
For the unintentional second-degree murder charge, prosecutors have to prove Mr Chauvin’s conduct was a “substantial causal factor” in Floyd’s death, and that Mr Chauvin was committing felony assault at the time. For third-degree murder, they must prove that Mr Chauvin’s actions caused Floyd’s death and were reckless and without regard for human life.
The manslaughter charge requires proof that Mr Chauvin caused Floyd’s death through negligence that created an unreasonable risk.
Unintentional second-degree murder is punishable by up to 40 years in prison, and third-degree carries up to 25 years, but sentencing guidelines suggest that Mr Chauvin would face 12 and a half years in prison if convicted on either charge.
Manslaughter is punishable by up to 10 years.