During the trial of former Minneapolis police officer Derek Chauvin on Thursday, Martin Tobin, a pulmonologist and breathing expert, testified George Floyd died due to a "low level of oxygen." He said a person in good health would have died by the restraint Chauvin used, rebutting his lawyer's arguments that Floyd died of health issues and drug use. Tobin also testified the trace amounts of fentanyl and methamphetamine in Floyd's system would not "have an effect on respiration." Previously, Jody Stiger, a use-of-force expert, testified that Chauvin used his body weight to pin Floyd's neck to the ground for more than nine minutes, using a "pain compliance technique" beyond the point Floyd stopped resisting. Chauvin, 45, is facing murder and manslaughter charges in the death of Floyd, a 46-year-old Black man.

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