MINNEAPOLIS (FOX 9) - The state continued to call expert medical witnesses to testify Friday in the trial of Derek Chauvin, the former Minneapolis police officer charged in the death of George Floyd. The trial is being broadcast live, gavel to gavel, on FOX 9 and streaming live at fox9.com/live.
Hennepin County Medical Examiner Dr. Andrew Baker took the stand after the lunch recess. He performed the official autopsy on Floyd, finding Floyd died of a cardiopulmonary arrest while being restrained by law enforcement, but also listing drugs and underlying health conditions as significant factors. His report ruled Floyd's death a homicide.
Chauvin is charged with third-degree murder, second-degree murder and second-degree manslaughter in Floyd’s death last May.
Friday was the first time during the trial the seat reserved for Chauvin's family has been filled. Sources told FOX 9 the woman in the courtroom for Chauvin was a family friend. Both the Floyd family and the Chauvin family are only allowed one seat in the courtroom due to COVID-19 restrictions.
Restraint was 'more than Mr. Floyd could take'
Throughout his testimony, Dr. Baker stood by his initial conclusion that Floyd’s death was a homicide and continued to reiterate that it was not drugs or Floyd’s underlying heart conditions that caused his death, it was heart and lung failure from the positioning of the officers on his neck and body.
During defense attorney Eric Nelson’s questioning of Dr. Thomas, it was revealed that Floyd had a slightly enlarged heart. Dr. Baker said Floyd had severe underlying heart disease and hypertensive heart disease, meaning his heart weighed more than it should.
Based on its size, Baker said Floyd’s heart already need more oxygen than a normal heart, and would be "limited in its ability to step up to provide more oxygen when there’s demand," such as when he was being restrained and Chauvin was kneeling on his neck.
"In my opinion, the law enforcement subdual, restraint and the neck compression was just more than Mr. Floyd could take by virtue of those heart conditions," Baker said.
Baker admitted under Nelson’s cross-examination, however, that the placement of Chauvin’s knee would not, anatomically, cut off Floyd’s airway.
Nelson drilled Baker on Floyd’s fentanyl levels at his time of death and how he has certified overdose deaths for lower amounts than those in Floyd’s body. Baker explained fentanyl was one of the factors that played a role in Floyd’s death, but did not cause his death.
"Mr. Floyd’s use of fentanyl did not cause the subdual or the neck restraint," Baker said. "His heart disease did not cause the subdual or the neck restraint."
Floyd was diagnosed with COVID-19 in April, but Baker said COVID-19 did not factor into his cause of death determination because "I didn’t see any signs of COVID-19 at his autopsy."
"To the best of my knowledge he was relatively healthy on May before the events of that evening, I’m unaware he was suffering from any acute COVID symptoms at that time," said Baker.
Veteran forensic pathologist concurs with ME's cause of death for Floyd
The first witness to take the stand Friday was Dr. Lindsey Thomas, a forensic pathologist who retired from the Hennepin County Medical Examiner’s Office in 2017. Dr. Thomas testified the state reached out to her for her opinions on Floyd’s cause of death, but she is not being paid to testify.
Dr. Thomas helped train Dr. Baker, the medical examiner who ruled Floyd’s death a homicide. She told the jury she concurs with Dr. Baker’s findings that Floyd died of cardiopulmonary arrest due to law enforcement subdual, restraint and neck compression. She said the primary mechanism was asphyxia, or low oxygen.
Thomas said it is normal practice for a medical examiner to seek out video of the incident, but noted she has never had a case where the death is so thoroughly documented, including video. She said in this case, the videos of Floyd’s deadly arrest led to her conclusion regarding his cause of death.
The autopsy helped rule out other causes of deaths, such as lung disease, neck injuries or a heart attack or stroke. Based on her review of the video, she also ruled out a cardiac arrhythmia or a drug overdose.
"There was nothing sudden about his death," Thomas said, which is what would have been expected if Floyd died from a cardiac arrhythmia or abnormal beating of the heart.
Thomas said it was not a fentanyl overdose death where someone "becomes very sleepy and then gradually, calmly, peacefully stops breathing."
"This was not that kind of death," she said.
Thomas ultimately concluded law enforcement actions led to Floyd’s death.
"I could clearly see from watching the video, what happens to Mr. Floyd during this subdual restraint and compression and what happens to his breathing is that it becomes it gradually becomes more difficult and then it stops."
When asked whether she believes Floyd would have died that night if he was not being restrained by law enforcement, Dr. Thomas said, "there is no evidence to suggest he would have died that night except for the interactions with law enforcement."
Medical experts testify Floyd died of loss of oxygen to body
Two expert witnesses testified on Thursday that, in their medical opinions, George Floyd died of a loss of oxygen to the body.
Dr. Martin Tobin, one of the nation’s foremost experts in the science of breathing, was on the stand for most of the day. He is an expert witness for the state, but was not paid to testify.
Tobin said he reviewed the medical records related to the case as well as videos of the deadly arrest and concluded Floyd "died from a low level of oxygen" that caused brain damage and a PEA (pulseless electrical activity) arrhythmia that caused his heart to stop.
Tobin said Floyd’s low oxygen level was caused by shallow breathing. He testified that a number of forces led to that shallow breathing, including him being in a prone condition, handcuffed and with a knees on his back and neck. That would have prevented air from being able to reach the "essential area in the bottom of the lungs where it gets oxygen into the blood and gets rid of the carbon dioxide," he said.
Dr. William Smock, a police surgeon and emergency room physician from Louisville, Kentucky, was a paid witness for the state. He testified that in his medical opinion, Floyd "died from positional asphyxia," or in simpler terms, he had "no oxygen left in his body."
Jurors also heard testimony from Dr. Daniel Isenschmid, a forensic toxicologist at the NMS Laboratory in Pennsylvania who ran tests on Floyd’s blood and urine from the autopsy.
Stay up to date on the trial of Derek Chauvin. Sign up for FOX 9's email newsletter for daily updates. Get breaking news alerts and watch the live stream in the FOX 9 News app. Download it for Apple or Android.