Do the autopsies of George Floyd agree, or not? News reports from last week suggest the report produced by the Hennepin County medical examiner and the one produced by an examiner hired by Floyd’s family disagreed on his cause of death. The county ruled the cause to be “cardiopulmonary arrest complicating law enforcement subdual, restraint, and neck compression.” It also cited heart disease and drug use as factors that could have contributed to the death. The secondary autopsy, by contrast, specifically said Floyd died from asphyxia.
So who is right? Well, both of them, experts who weren’t affiliated with the case said. In fact, according to forensic pathologists and medical experts, the two autopsy reports aren’t actually all that different in their conclusions. “They are just different ways of describing the same thing,” said Dr. Joye Carter, forensic pathologist to the sheriff of San Luis Obispo County, California. What’s more, experts told me, the autopsies of George Floyd help show the complexity of medical examinations, how those examinations work and what they can and cannot tell us.
Some of the public confusion over Floyd’s autopsy reports can be blamed on misinterpretation by the media and the public, said Dr. Judy Melinek, a San Francisco-based forensic pathologist . “Anybody suggesting asphyxia was ruled out by the medical examiner is wrong,” she said. Indeed, lots of people suggested just that, with media describing the reports as “drastically different” and nearly describing the county report as absolving the white police officer who pressed his knee into Floyd’s back for 8 minutes.
The Hennepin County autopsy may have mentioned factors beyond police conduct, but it was really just saying Floyd’s heart stopped while police were restraining him and pressing on his neck, said Melinek, Carter and Dr. Michael Freeman, professor of forensic medicine and epidemiology at Maastricht University in the Netherlands. It’s not a claim that he died of a heart attack, drugs, or pre-existing conditions, they told me. “The cause of death is police restraint,” Melinek said, just like in the autopsy Floyd’s family commissioned.
The reason it might seem like the exams disagree, they said, is because people expect a single cause of death in an autopsy report. But most people don’t die from just one thing. Instead, both death certificates and autopsy evaluations are set up to tell as detailed a story as possible — death happened, as a result of something, complicated by another thing, and maybe with other factors that were present. You’re supposed to compile the full chain of events and all the possible compounding factors. But documenting potential contributing factors isn’t the same as saying that’s what caused the death.
These reports — and the public confusion around them — also highlight how complex forensic pathology can really be. Take the confusion over asphyxiation. As he was dying, Floyd told the police officers that he couldn’t breathe, eventually stopped speaking and then went limp. So it surprised a lot of people when the autopsy reports came across as saying that they’d found no evidence of asphyxiation.
That is both a misunderstanding of the report and an example of the difficulty in identifying cause of death, experts said. It’s a misunderstanding because an earlier legal document, put out to explain the charges against the officer who kneeled on Floyd, said the county had found no injuries consistent with asphyxia caused by physical trauma. But the actual autopsy report doesn’t mention the word “asphyxia” at all. It does, however, describe “neck compression” as a direct cause of Floyd’s death — meaning the blood flow (and, thus, oxygen) to Floyd’s brain and heart were cut off. It doesn’t take physical trauma to asphyxiate someone.
And that’s where the difficulty of pinning down cause of death comes in, said Dr. Karl Williams, a forensic pathologist who is the chief medical examiner of Allegheny County (home to Pittsburgh), Pennsylvania. “After that video we know why he died,” Williams said. “But it doesn’t necessarily mean, OK, that there’s going to be any evidence of that.” You can make someone lose consciousness just by compressing the arteries and veins in their neck, cutting off blood flow to and from the brain, he told me. Williams said he has watched experts demonstrate this effect at conferences. People will lose consciousness after 7-to-10 seconds, he said. “It’s very reproducible. We vary on where the point of no return would be, but if you block those veins for three to four minutes, you’re dead.”
But there’s no medical literature of what happens to a person’s body when someone kneels on their neck for more than eight minutes, as Derek Chauvin, the Minneapolis police officer now charged with second-degree murder, did to Floyd. So no medical examiner can call up that data and compare it to what they found in Floyd’s body, Williams told me. The result, he said, has been whole listserves full of medical examiners going over the evidence in the Floyd case and arguing back and forth for the past week about how they would write the report. “There certainly is individual variety,” Carter said. “Medicine is a practice and everything isn’t rubber stamped the same way.”
Everybody agrees Floyd’s death was a homicide, Williams told me. But when you get to the specific cause of death, and the order of priority of multiple causes, subjectivity comes into play. “If you were to present that video to 100 different board certified forensic pathologists, you’d get 20, 30, 40 different ways of turning that into the statement of death,” he said. “This happens with about 5-to-10 percent of the cases we do.”
Another good example of an issue where forensic pathologists don’t agree: the existence of a controversial diagnosis — “excited delirium” — which was discussed by the officers at the scene of Floyd’s death. (Neither of Floyd’s autopsies mentioned the condition and none of the experts I spoke to believe it applies to him.) The basic idea behind excited delirium is that someone who is high on stimulants, such as cocaine or methamphetamines, can get into a place where their mind is no longer functioning normally. “They become agitated and violent and hyperthermic, so their body temperature goes up and they undress and act inappropriately. They might break glass and be unaware of their environment. They’re hallucinating,” Melinek said. That situation can often lead to someone being restrained by multiple police officers while they fight back violently. Sometimes the person dies — and the death ends up attributed to excited delirium, rather than to the restraint.
Melinek, Carter and Williams all believe this is a real diagnosis that really does cause death in some situations — though Carter added that restraint can contribute to those deaths. But Freeman isn’t so sure excited delirium is a legitimate cause of death. The dead people diagnosed with it tend to be young, black males who died in police custody, he said. “There’s been cases where the [medical examiner] has done an exam, found 12 broken ribs, a history of extreme restraint and all sorts of things going on,” he said. “But they find a relatively small amount, a recreational level of methamphetamine in the blood and they say, ‘Oh it’s excited delirium.’ Which completely exculpates the law enforcement from causing the death, which they clearly did.” Freeman’s research team currently has a paper in the process of being published that reviews scientific studies comparing excited delirium with cases of agitated delirium syndrome — a medical diagnosis that gets applied more by doctors treating a person who lived, while excited delirium is primarily used by forensic pathologists examining a person who died.
While both syndromes present with roughly the same symptoms, Freeman’s team found that restraint was used in 90 percent of the cases that turned out to be fatal. Only 2 percent of fatal cases involved no restraints. (The rest were unknown.) Forceful restraints such as manhandling or hog-tying were also significantly more likely in fatal cases. The point, Freeman said, is that there’s evidence it’s not the excited delirium that kills people. It’s the way they are restrained.
All the experts I spoke to see no evidence of excited delirium in Floyd’s case. In the video of his death, Melinek pointed out, you can clearly see that he is not sweating excessively, nor is he dressed inappropriately. He communicates clearly with officers and bystanders and is coherent even as he is pleading for his life. But the fact that one of the officers at the scene suggested this diagnosis, and that legal scholars believe it will come up in Chauvin’s defense, demonstrates how medical analysis can be used in cases like this. And how disagreement among forensic pathologists about how to describe the evidence in a case can muddy the legal waters.
“There are very few checks and balances, and that’s really the issue here,” Freeman said. “There’s nobody to second guess your work [as a medical examiner]. If there is somebody doing something in a biased fashion — systematically always doing it wrong … it’s disadvantaged populations who are getting these diagnoses.”