Expert Witness Pinpoints Floyd’s Final Breath and Dismisses Talk of Overdose

A pulmonologist told jurors that Derek Chauvin pressed 86.9 pounds onto the neck of George Floyd, who tried to push himself off the pavement with his fingertips.

MINNEAPOLIS — It was a video everyone in the courtroom has been shown repeatedly, of George Floyd facedown on the street with Derek Chauvin’s knee on his neck. But this time, it was slowed down so the jury could see the briefest widening of Mr. Floyd’s eyes — what the expert witness on the stand on Thursday said was his last conscious moment. “One second he’s alive, and one second he’s no longer,” said the witness, Dr. Martin Tobin, adding, “That’s the moment the life goes out of his body.” Dr. Tobin, a pulmonologist who specializes in the mechanics of breathing, presented the prosecution’s first extended testimony on a central question in the murder trial of Mr. Chauvin: how George Floyd died. “You’re seeing here fatal injury to the brain from a lack of oxygen,” Dr. Tobin said.