The three former Minneapolis police officers on trial for violating George Floyd’s civil rights stood by as fellow officer Derek Chauvin "slowly killed George Floyd right in front of them," prosecutors charged during Monday’s opening statements. 

One defense attorney countered that Chauvin called "all of the shots" as the senior officer at the scene, and criticized the Minneapolis Police Department for doing too little to train officers to intervene when a colleague should be stopped.

Former officers J. Alexander Kueng, Thomas Lane and Tou Thao are broadly charged with depriving Floyd of his civil rights while acting under government authority. Floyd died on May 25, 2020, after Chauvin pressed him to the ground with his knee on Floyd’s neck for 9 1/2 minutes while the 46-year-old Black man was facedown, handcuffed and gasping for air. Kueng knelt on Floyd’s back and Lane held down his legs. Thao kept bystanders from intervening in the videotaped killing that triggered worldwide protests, violence and a reexamination of racism and policing.

FILE - This combination of photos provided by the Hennepin County Sheriff's Office in Minnesota on  June 3, 2020, shows, from left, former Minneapolis police officers J. Alexander Kueng, Thomas Lane and Tou Thao. 

FILE - This combination of photos provided by the Hennepin County Sheriff's Office in Minnesota on  June 3, 2020, shows, from left, former Minneapolis police officers J. Alexander Kueng, Thomas Lane and Tou Thao.  (Hennepin County Sheriff's Office via AP, File)

Kueng, who is Black; Lane, who is White; and Thao, who is Hmong American, are all charged with failing to provide Floyd with medical care. Thao and Kueng face an additional count for failing to stop Chauvin, who was convicted of murder and manslaughter in state court last year. Both counts allege that the officers’ actions resulted in Floyd’s death.

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"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," prosecutor Samantha Trepel told jurors during opening statements. "They chose not to protect George Floyd, the man they had handcuffed and placed in their custody."

Tom Plunkett, the attorney for Kueng, highlighted the rookie status of his client and Lane. He said both men deferred to Chauvin and called him "sir."

FILE - In this image from police body camera video former Minneapolis police Officer Derek Chauvin stands outside Cup Foods in Minneapolis, on May 25, 2020, with a crowd of onlookers behind him. 

FILE - In this image from police body camera video former Minneapolis police Officer Derek Chauvin stands outside Cup Foods in Minneapolis, on May 25, 2020, with a crowd of onlookers behind him.  (Court TV via AP, Pool, File)

"You’ll see and hear officer Chauvin call all of the shots," Plunkett said.

Attorneys for both Kueng and Thao noted that prosecutors must prove that Kueng, Lane and Thao willfully violated Floyd’s constitutional rights.

Trepel said videos will show that Thao stood directly next to Chauvin, but instead of intervening, he taunted Floyd for using drugs, telling bystanders, "This is why you don't" use drugs.

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She said Kueng "never once" told Chauvin to get off Floyd, even after Floyd stopped struggling and even after Kueng twice could not find a pulse. Instead, she said, Keung remained kneeling on Floyd.

Lane asked if they should roll Floyd onto his side — something all the officers were trained to do — but Kueng shot down Lane’s question and said, "No, just leave him," and Chauvin agreed, Trepel said.

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Last week, 18 people were swiftly chosen for the jury; 12 will deliberate and six will be alternates. Two of the jurors — one expected to deliberate and one alternate — appear to be of Asian descent. The rest appear to be White. The jurors include people from the Twin Cities area, the suburbs and southern Minnesota. The court declined to provide demographic information.

FILE - This image from video shows Minneapolis police Officers Thomas Lane, left and J. Alexander Kueng, right, escorting George Floyd, center, to a police vehicle outside Cup Foods in Minneapolis, on May 25, 2020. 

FILE - This image from video shows Minneapolis police Officers Thomas Lane, left and J. Alexander Kueng, right, escorting George Floyd, center, to a police vehicle outside Cup Foods in Minneapolis, on May 25, 2020.  (Court TV via AP, Pool, File)

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U.S. District Judge Paul Magnuson told jurors that the trial could last four weeks. It’s not known whether any of the three officers will testify. It’s also not clear whether Chauvin will testify.

Lane, Kueng and Thao also face a separate state trial in June on charges they aided and abetted both murder and manslaughter.

The Associated Press contributed to this report.