Derek Chauvin will not testify, defense rests case as closing arguments scheduled for Monday

10:45 a.m.

After a short break, the court has reconvened. Nelson starts cross-examination of Dr. Tobin. After a brief questioning, Tobin is excused.

The state rests.

Closing arguments will start on Monday, according to Cahill.

10:15 a.m.

The court has reconvened. The defense officially rests its case. The state recalls Dr. Martin Tobin to the witness stand.

He says he doesn’t agree with that statement made by Fowler, "based on the arterial blood gas that was obtained when Mr. Floyd was in Hennepin County." Nelson objected, and Cahill sustained. He asked Blackwell to rephrase the question.

Fowler made an opinion Wednesday that the potential elevation of 10 to 18% in Floyd’s blood in relation to carbon monoxide poisoning.

Cahill has put the court in recess until 10:45 a.m.

9:15 a.m.

The court has convened for the day.

Chauvin has made the court aware that he will not testify in this case, choosing to invoke his Fifth Amendment privilege.

The defense will rest its case Thursday with the state planning to call rebuttal witnesses to address some "newly discovered evidence."

State prosecutor Jerry Blackwell says the state has blood gas evidence from Hennepin County "that would contain blood gas reading for the carbon monoxide content in Mr. Floyd’s blood on May 25, 2020." He adds the state was just notified of this evidence on carbon monoxide Wednesday. According to Blackwell, Hennepin County Medical Examiner Dr. Andrew Baker discovered it.

The state is moving to bring back Dr. Martin Tobin, the Chicago pulmonologist, to re-take the witness stand as a rebuttal witness. Nelson is objecting, as it would be a move to bring back Tobin to "talk about what he already talked about."

Blackwell states they wouldn’t be having these discussions if it weren’t for Dr. Fowler’s testimony on Wednesday.

"Dr. Tobin will not testify as to those lab results, if there’s anything he wishes to add about carbon monoxide as far as environmental factors, but if he hints that there are test results, the jury has not heard about, it’s going to be a mistrial, pure and simple," Judge Peter Cahill told the court.

Dr. Martin Tobin will take the witness stand after a short break. Cahill has put the court in recess until 10:15 a.m.

The defense could wrap up their arguments as soon as Thursday in the trial of former Minneapolis police officer Derek Chauvin.

On Wednesday, defense testimony included a single witness.

Dr. David Fowler, a former Maryland chief medical examiner who is now with a consulting firm, was on the stand for seven hours.

He told jurors he believed George Floyd died of a sudden heart rhythm disturbance as a result of his heart disease

That contradicted prosecution experts who said Floyd succumbed to a lack of oxygen from the way he was pinned down.

Fowler also said the fentanyl and methamphetamine in Floyd’s system, and possibly carbon monoxide poisoning from auto exhaust, were contributing factors in the Floyd’s death last May.

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Fowler also testified that he would classify the manner of death "undetermined," rather than homicide, as the county’s chief medical examiner ruled. He said Floyd’s death had too many conflicting factors, some of which could be ruled homicide and some that could be considered accidental.

Chauvin attorney Eric Nelson is trying to prove that the 19-year Minneapolis police veteran did what he was trained to do and that Floyd died because of his illegal drug use and underlying health problems.

Prosecutors say Floyd died because the white officer’s knee was pressed against Floyd’s neck or neck area for 9 1/2 minutes as he lay on the pavement on his stomach, his hands cuffed behind him and his face jammed against the ground.

Fowler listed a multitude of factors or potential ones: Floyd’s narrowed arteries, his enlarged heart, his high blood pressure, his drug use, the stress of his restraint, the vehicle exhaust, and a tumor or growth in his lower abdomen that can sometimes play a role in high blood pressure by releasing "fight-or-flight" hormones.

Fowler said all of those factors could have acted together to cause Floyd’s heart to work harder, suffer an arrhythmia, or abnormal rhythm, and suddenly stop.

Prosecutor Jerry Blackwell launched an aggressive cross-examination, attacking Fowler’s findings down the line. He got Fowler to acknowledge that even someone who dies from being deprived of oxygen ultimately dies of an arrhythmia.

He also got Fowler to admit that he didn’t take the weight of Chauvin’s gear into account when he analyzed the pressure on Floyd’s body. Blackwell further accused Fowler of jumping to conclusions and suggesting to the jury that Floyd had a white pill in his mouth in the video of his arrest. Fowler denied saying that.

Blackwell also attacked Fowler’s testimony about carbon monoxide, which displaces oxygen in the bloodstream.

In his original testimony, Fowler said carbon monoxide could have contributed to oxygen depletion in Floyd, noting that he was facing the tailpipe end of a squad car. But Floyd’s blood was never tested for carbon monoxide.

"You haven’t seen any data or test results that showed Mr. Floyd had a single injury from carbon monoxide. Is that true?" Blackwell asked.

"That is correct, because it was never sent," Fowler said.

Blackwell also noted that the squad car was a gas-electric hybrid and that Fowler had no data on how much carbon monoxide was actually released. And he suggested that the witness assumed the engine was running at the time. Fowler said he believed it was.

The prosecutor also got Fowler to agree that it would take four minutes to cause irreversible brain damage if the brain is starved of oxygen, and that insufficient oxygen can cause the heart to stop.

"And if a person dies as a result of low oxygen, that person is also going to die ultimately of a fatal arrhythmia, right?" Blackwell asked.

Fowler responded: "Correct. Every one of us in this room will have a fatal arrhythmia at some point."

Fowler further agreed that Floyd should have been given immediate attention when he went into cardiac arrest because there still was a chance to save him at that point.

A number of medical experts called by prosecutors have said Floyd died from a lack of oxygen because his breathing was constricted by the way he was held down. A cardiology expert rejected the notion that Floyd died of heart problems, saying all indications were that he had "an exceptionally strong heart."

But Fowler said that Chauvin’s knee on Floyd was "nowhere close to his airway" and that Floyd’s speaking and groaning showed that his airway was still open. He also testified that Chauvin’s knee was not applied with enough pressure to cause any bruises or scrapes on Floyd’s neck or back.

And he said that Floyd did not complain of vision changes or other symptoms consistent with hypoxia, or insufficient oxygen to the brain, and that he was coherent until shortly before he suddenly stopped moving.

"The bottom line is, moving air in and out, and speaking and making noise is very good evidence that the airway was not closed," Fowler said.

Blackwell ended his cross-examination by getting two questions before the jury: Whether Chauvin’s actions played a role in Floyd’s death, or whether Floyd’s death was coincidental and unrelated. But the defense objected, and Fowler was not permitted to answer.

Chauvin is charged with murder and manslaughter in connection with Floyd’s death.

The defense hasn’t said whether Chauvin will take the stand.