A focus on medical testimony and George Floyd’s cause of death in the Derek Chauvin trial Thursday.
A medical expert testified George Floyd died from a lack of oxygen that damaged his brain and caused his heart to stop.
Dr. Martin Tobin is a lung and critical care specialist from Chicago. He testified that Floyd's breathing was too shallow to take in enough oxygen while he was pinned on his stomach with his hands cuffed behind his back for 9 1/2 minutes.
Tobin said the low level of oxygen was due to a knee on his neck and added that the handcuffs were also constricting.
"It's how they are being held, being pushed upwards, that totally interferes with features on how we breathe,” Tobin said.
Tobin focused his attention on the first 5 minutes and 3 seconds of the tape, describing in great detail, the anatomy of a person's neck and how Chauvin's knee was pressed on a particularly delicate part of Floyd's neck.
“They were forcing his left wrist to his chest, forcing it up high, and you have to keep in mind that the opposite side of this is the street, so he was being squashed between the two sides,” he said.
At one point he said there was virtually no oxygen in Floyd's left lung and a surgeon could have gone in and removed it.
"A healthy person subjected to what Mr. Floyd was subjected to would have died," Tobin said.
A police surgeon in Louisville and forensic scientist testified that Floyd died due to positional asphyxia, “which is a fancy way of saying he died because he had no oxygen left in his body,” Dr. Bill Smock, a state expert witness, testified.
Floyd did not die from the controversial diagnosis of excited delirium, Tobin said, because he did not display symptoms such as superhuman strength, destruction of mirrors and glass, and rapid breathing. Smock also rejected a fentanyl overdose cause, saying that people dying of fentanyl will descend into a sleep state, while Floyd was oriented and responsive.
Both Smock and Tobin pointed out Floyd, while prone and handcuffed behind his back on the ground, used his knuckles and fingers to try to leverage his chest up— any resource available to try to breathe.
On cross-examination, Chauvin’s attorney Eric Nelson asked Smock if he’s seen officers he works with conduct arrests in the prone position. Smock responded yes, “for short periods of time.”
Friday, to wrap up the second week of testimony, a critical witness for both the prosecution and defense takes the stand: Dr. Andrew Baker, the Hennepin County Medical Examiner who conducted Floyd’s autopsy.