ST. PAUL, Minn. — A former Minneapolis police officer charged in George Floyd’s killing testified Thursday that he didn’t act on another officer’s suggestion to roll Floyd on his side after he stopped breathing, didn’t ask Officer Derek Chauvin to check for a neck pulse and didn’t try to get Chauvin off Floyd’s neck.

In this courtroom sketch, former Minneapolis police officer J. Alexander Kueng testifies during his trial in the killing of George Floyd, in federal court in St. Paul, Minn., on Wednesday. Cedric Hohnstadt via Associated Press

J. Alexander Kueng is one of three former officers charged in federal court with violating Floyd’s constitutional rights when Chauvin pressed his knee into Floyd’s neck for 9½ minutes as the 46-year-old Black man was handcuffed, facedown on the street and pleading for air before going silent. Kueng knelt on Floyd’s back, Thomas Lane held his legs and Tou Thao kept bystanders back.

Prosecutor Manda Sertich peppered Kueng with questions about his training, including on material from an emergency medical responder course he took that said someone might not be breathing adequately even though they’re talking and then lists thing to check for.

She pointed out that Floyd stopped talking after about 4½ minutes and asked if it was a “red flag.”

“It is something to reassess, yes ma’am,” replied Kueng, who later agreed that he was trained to roll someone on their side to help them breathe when it was safe to do so.

But Kueng said he didn’t do so at Lane’s suggestion after Floyd passed out, or in the five minutes that officers kept him restrained afterward. Kueng said he checked Floyd’s wrist pulse twice and couldn’t find one, then told Chauvin, but didn’t try to check Floyd’s neck pulse himself.

All three officers are accused of depriving Floyd of his right to medical care. Prosecutors have argued that the officers violated their training by not rolling Floyd onto his side or giving him CPR.

Kueng and Thao are also accused of failing to intervene to stop Chauvin in the May 25, 2020, killing that triggered protests worldwide and a re-examination of racism and policing.

Defense attorneys contend the Minneapolis Police Department provided inadequate training and taught cadets and rookies to obey superiors. They have also said that Chauvin, who was convicted of state murder and manslaughter charges last year, called the shots that day.

A retired Springfield, Missouri, assistant police chief testified that the Minneapolis Police Department’s training on an officer’s duty to intervene to stop other officers from using excessive force was ineffective because it relied too heavily on lectures instead of hands-on training and testing to ensure that trainees learn the right lessons.

Steve Ijames, a use-of-force expert, also said that Kueng did not use unreasonable force to help hold down Floyd. But he said that Chauvin’s continued force after Floyd stopped fighting was unreasonable — “beyond question.”

He also said Kueng lacked the training and experience to recognize Chauvin’s inappropriate use of force and that it made sense for Kueng to defer to Chauvin, a 19-year veteran who had been his field training officer.

Kueng testified Wednesday that he deferred to Chauvin because he was his senior officer and that’s what he was trained to do. Kueng and Lane were both rookies, with just a few days working without a trainer.

“He was my senior officer and I trusted his advice,” said Kueng, who has said he feared he could be fired for disobeying a superior.

Under questioning from Sertich, Ijames said it’s conceivable Kueng could have walked around and checked the neck without moving or disturbing Chauvin.

A retired Minneapolis Police Department lieutenant and field training officer testified that it made sense that the other officers let Chauvin take charge of the scene, especially since Lane and Kueng were rookies. “Somebody needs to be in charge” and there isn’t always time to deliberate, Gary Nelson said.

Under cross-examination by prosecutor Samantha Trepel, Nelson agreed that officers aren’t obligated to follow clearly unlawful orders and that they’re accountable for both their actions and their inactions.

Thao testified this week that he relied on the other three officers scene to care for Floyd’s medical needs while he controlled the crowd and traffic and that he didn’t think Chauvin’s knee was on Floyd’s trachea.

Lane is also expected to testify at the trial that is scheduled to resume on Monday.

Lane, who is white; Kueng, who is Black; and Thao, who is Hmong American, also face a separate state trial in June on charges alleging that they aided and abetted murder and manslaughter.

Chauvin, who is white, pleaded guilty in December to a federal civil rights charge.