At Chauvin trial, expert says Floyd died from ‘low level of oxygen’ after officer had knee on neck

Testimony in the trial of former Minneapolis police officer Derek Chauvin continued Thursday with a breathing expert saying that George Floyd died due to a “low level of oxygen” that caused brain damage, rebuking the defense’s argument that drugs contributed to Floyd’s death. Martin Tobin, a pulmonologist and national breathing expert from Hines, Ill., offered testimony as an unpaid witness that Chauvin’s knee was on Floyd’s neck for the “vast majority of the time” and that the pain from the pressure applied by the officer to Floyd was comparable to that of a surgery to remove a lung.

During his testimony, Tobin said a person in good health would have died from the restraint administered by Chauvin, saying the officers manipulated the handcuffs on Floyd in a way that had the 46-year-old in a “vise” grip.

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Chauvin attorney Eric J. Nelson again put focus on the traces of fentanyl and methamphetamine that were found in Floyd’s body as a contributing factor to his restricted breathing.

Tobin estimated that Chauvin placed more than 91 pounds on Floyd’s neck.

When police officers pressed on the left side of Floyd’s body, the pain was not that much different from the pressure felt in removing a lung, Tobin testified.

Floyd’s airways were 85 percent restricted, Tobin said, thus making breathing “at some stage unsustainable.”

Tobin, who is not a paid witness, rebuked the defense’s stance that “if you can speak, you can breathe,” calling that position “a very, very dangerous mantra.”