A prosecutor and defense attorneys made opening statements Monday morning in the civil rights case of three former Minneapolis officers, forecasting a trial that will hinge on what the men thought and saw as Derek Chauvin knelt on George Floyd's neck for more than nine minutes.

In St. Paul's federal courthouse, Assistant U.S. Attorney Samantha Trepel described how Tou Thao, Thomas Lane and J. Alexander Kueng ignored obvious signs of grave distress in Floyd, whom they'd taken into custody. They continued to neglect their training and legal obligation to render medical aid as the window to save Floyd's life "slammed shut," Trepel said.

"Here, on May 25, Memorial Day 2020, for second after second, minute after minute, these three CPR-trained defendants stood or knelt next to officer Chauvin as he slowly killed George Floyd right in front of them," Trepel said.

The opening statements offered for the first time a window into the defense strategy, and a revelation that at least Lane plans to testify. In three separate introductory remarks, the defense attorneys described a hectic and at times scary situation in which the officers encountered a towering, erratic suspect who resisted their commands.

Thomas Plunkett, attorney for Kueng, called his client a "rookie officer" who was failed by the Minneapolis Police Department's inadequate training. He said Kueng saw only what was right in front of him and lacked the full context of the wide-view of bystander video that went viral. "That video is not what Alex Kueng saw," Plunkett said. "It's not what Alex Kueng perceived, and it's not what he experienced on May 25, 2020."

Signaling a contentious trial ahead, Plunkett called for a mistrial within the first 90 minutes of court, saying Trepel made inappropriate argumentative remarks in her opening statement. Judge Paul Magnuson rejected Plunkett's request.

'In your custody is in your care'

The first to address the jury, Trepel said that when police officers take a person into their custody, they become responsible for the person's safety.

"In your custody is in your care," Trepel said, a concept at the heart of the prosecution's case. "It's not just a moral responsibility — it's what the law requires under the U.S. Constitution."

Trepel said that "signing up to carry a gun and wear a badge comes with life-or-death duties," and the officers received lengthy training on how to identify and respond to a medical emergency. Instead, these officers made a "conscious choice over and over again not to act."

Thao's attorney, Robert Paule, began his opening statement by calling Floyd's death a "tragedy," but said "a tragedy is not a crime."

Paule said the officers arrived at Cup Foods to investigate a report of a man trying to pass a counterfeit $20. They encountered a suspect outside in his vehicle, who ignored their commands, acted erratically and physically resisted arrest, he said.

Plunkett said that when Chauvin, the senior officer, showed up, he took charge and became the "shot-caller."

He said Chauvin had served as Kueng's training officer for longer than he should have, per department protocols. "The [training officer] has great control over a young officer's future in the Minneapolis Police Department," he said.

Specifically calling out former Minneapolis Police Chief Medaria Arradondo, Plunkett said the "academy training on 'intervention' is little more than a word on a PowerPoint."

To find Kueng guilty, prosecutors must show he acted "willfully" to disobey the law and deprive Floyd of his rights, Plunkett said. "Mr. Kueng is not guilty if the government fails to show knowledge of specific medical need and deliberate disregard," he said.

Earl Gray, the attorney for Lane, said the officers found themselves in a "scary" situation when Floyd reached around in the console of his vehicle for what they feared could be a gun. Gray described Floyd as 6 foot 4, 225 pounds and physically combative. "He was all muscle," Gray said.

He said Lane tried to revive Floyd and raised the prospect of turning him on his side as Chauvin stayed on his neck. He described Lane as "not deliberatively indifferent about his health at all."

Concluding his comments, Gray called the state's case against Lane a "perversion of justice."

After opening statements, the government called its first witness, FBI forensic media examiner Kimberly Meline, and played footage from Lane's body-worn camera as he approached Floyd's vehicle and drew his gun.

"Keep your … hands on the wheel," Lane shouted, swearing at Floyd.

"Please don't shoot me," Floyd pleaded.

Moments later, as the officers tried to push Floyd into the back of a squad, Floyd resisted, saying he was "scared" and "claustrophobic."

"I'm not a bad guy, man," he said as he struggled with officers.

Instead, the officers held him down on the ground next to the police vehicle.

"I can't breathe," repeated Floyd. The video played for more than 20 minutes as Floyd eventually went silent and motionless. At the end, the video captured Lane's hands as he gave chest compressions to Floyd inside the ambulance.

Jurors will decide which to believe

Chauvin pleaded guilty in December to the federal charges and is now serving a 22½-year state sentence after being convicted in Hennepin County District Court of murder for kneeling on Floyd's neck for more than nine minutes while detaining him on the pavement at 38th and Chicago.

Jury selection was completed in one day for the trial of Thao, Kueng and Lane. Twelve jurors and six alternates were selected from a pool of 67 questioned in two groups by Magnuson. Because this is a federal trial, the jurors come from all over the state.

The identities of the jurors are not publicly known. Two of the jurors appeared to be Asian and the rest are white.

Thao, Kueng and Lane also are charged in state court with aiding and abetting murder in connection with Floyd's death. Hennepin County District Judge Peter Cahill on Wednesday moved that trial's start date from March 7 to June 13 after defense attorneys and prosecutors asked for a postponement.

Star Tribune staff writer Paul Walsh contributed to this report.