AdvertisementChauvin Trial: Expert Says George Floyd Died From A Lack Of Oxygen, Not FentanylUpdated April 08, 2021Bill ChappellVanessa RomofacebookEmailDr. Martin Tobin testifies Thursday in the murder trial of former police officer Derek Chauvin. Tobin told jurors that the way George Floyd was restrained effectively shut down his left lung. (Court TV/Pool via AP)This article was originally published on April 08, 2021.