In George Floyd’s case, “I believe the primary mechanism of death is asphyxia or low oxygen,” Dr. Lindsey Thomas, a forensic pathologist, told jurors in the trial of former Minneapolis police officer Derek Chauvin.

In this image from video, Dr. Lindsey Thomas, a forensic pathologist, now retired, testifies as Hennepin County Judge Peter Cahill presides Friday, April 9, 2021, in the trial of former Minneapolis police Officer Derek Chauvin at the Hennepin County Courthouse in Minneapolis. Chauvin is charged in the May 25, 2020 death of George Floyd. (Court TV via AP, Pool)