In June 2020, after the Hennepin County Medical Examiner released the complete autopsy report in the George Floyd case, I discussed its findings in two episodes of Tonight’s Political Economy on the Chinese-language network Mirror TV. The first, on June 6, was a solo review. The second, on June 13, was a discussion with Dr. Li, a forensic pathologist and medical examiner’s office director who has performed nearly 3,000 autopsies.
At the time, I questioned whether the report contained direct anatomic evidence of fatal asphyxia caused by neck compression. I also highlighted Floyd’s toxicology results and cardiovascular disease as possible contributing factors. Materials released later, including memoranda documenting conversations with Hennepin County Medical Examiner Dr. Andrew Baker, provide further context for those questions.
This article focuses on the forensic evidence. It does not attempt to determine legal responsibility or excuse the use of force.
What the autopsy established
The medical examiner listed the cause of death as “cardiopulmonary arrest complicating law enforcement subdual, restraint, and neck compression.” The manner of death was classified as homicide.
That wording identifies the restraint and neck compression as factors in the chain of events leading to death. It does not specify asphyxia as the mechanism. In forensic medicine, homicide means that another person’s actions contributed to a death; it is not equivalent to a legal finding of murder.
Under “Diagnoses,” the report states: “No life-threatening injuries identified.” It documented:
No petechiae of the face, conjunctivae, or oral mucosa
No hemorrhage in the anterior or posterior neck muscles
No fracture or deformity of the laryngeal structures
No injury to the scalp, skull, or brain
No injury to the chest wall, spine, or internal organs
No ischemic brain injury on microscopic examination
A single rib fracture was attributed to cardiopulmonary resuscitation.
These negative findings do not support a crushed airway or other traumatic neck injury. They also weigh against complete, sustained vascular obstruction. However, their absence does not exclude all forms of restraint-related breathing impairment. Functional restriction of ventilation may occur without fractures, hemorrhage, or other distinctive autopsy findings.
The autopsy must therefore be interpreted together with the circumstances, video evidence, medical history, and clinical course. Anatomic findings alone cannot always establish or exclude a functional mechanism of death.
Toxicology and cardiovascular disease
Hospital-admission blood contained fentanyl at 11 ng/mL and norfentanyl, its principal metabolite, at 5.6 ng/mL. Methamphetamine was detected at 19 ng/mL. Morphine was found in urine, and a urine cannabinoid screen was presumptively positive but unconfirmed. Ethanol testing was negative.
The autopsy report notes that fatal fentanyl cases have involved blood concentrations as low as 3 ng/mL. A 2017 report in the CDC’s Morbidity and Mortality Weekly Report described two fatal overdoses with postmortem fentanyl concentrations of 11 and 13 ng/mL.
This comparison shows that 11 ng/mL has occurred in fatal overdoses. It does not establish that this concentration is invariably fatal. Fentanyl toxicity varies according to tolerance, other substances, the sampling site, the interval between exposure and death, treatment, and postmortem redistribution.
The relationship between fentanyl and norfentanyl may be compatible with recent use, but the results cannot determine the precise timing of ingestion. Toxicology concentrations should not be interpreted in isolation.
Floyd also had substantial cardiovascular disease. The autopsy documented hypertensive heart disease, an enlarged heart weighing 540 grams and 75 percent narrowing of the left anterior descending coronary artery. Methamphetamine can increase cardiovascular stress, making its presence relevant in a person with severe underlying heart disease.
Together, the toxicology and cardiac findings identify plausible contributors to cardiopulmonary arrest. They do not establish that drugs and disease fully explain the death or that the restraint played no role.
Baker’s reported comments
Three memoranda later filed in court documented conversations with Baker around the time the autopsy was completed.
A May 26, 2020, memorandum states: “The autopsy revealed no physical evidence suggesting that Mr. Floyd died of asphyxiation. Mr. Floyd did not exhibit signs of petechiae, damage to his airways or thyroid, brain bleeding, bone injuries, or internal bruising.”
A June 1 memorandum records Baker describing the fentanyl concentration as “pretty high” and “a fatal level of fentanyl under normal circumstances.” It also states that, if Floyd had been found dead at home without other contributing factors, Baker would have classified the death as an overdose.
These comments require context. Baker’s hypothetical assessment indicates that the toxicology findings could have supported an overdose diagnosis under different circumstances. The actual case included prolonged restraint and other scene evidence, which he considered in his final certification.
The absence of physical evidence of asphyxia is also not necessarily incompatible with a finding that restraint contributed to death. A pathologist may identify a functional or physiological contribution without finding a specific traumatic lesion. Nevertheless, the memoranda show uncertainty about the precise mechanism and the relative importance of the competing factors.
Minutes from a subsequent meeting recorded forensic consultant Dr. Roger Mitchell as saying that neck compression “has to be in the diagnosis.” The same document states that Baker “didn’t think the neck compression played a part” and found no petechiae.
These excerpts suggest disagreement over the diagnostic wording. They do not establish that Mitchell dictated the final certification or that Baker signed a diagnosis he considered inaccurate. The full context and Baker’s explanation would be required to reach that conclusion.
What speech can – and cannot – show
During much of the restraint, Floyd remained able to speak, repeatedly saying, “I can’t breathe.”
Speaking requires airflow through the larynx and trachea. His ability to produce words therefore indicates that the airway was not completely obstructed at those moments. It does not prove that airflow, ventilation, or oxygenation was adequate. A person can speak while experiencing severe respiratory distress, partial airway obstruction, or other forms of breathing impairment.
The speech evidence should therefore be interpreted narrowly. It argues against complete mechanical closure of the trachea while Floyd was talking, particularly when considered alongside the absence of laryngeal fracture and neck hemorrhage. It does not exclude restricted breathing, impaired ventilation, or other physiological effects of restraint.
Similarly, the absence of petechiae does not rule out every asphyxial mechanism. Petechiae may occur with venous obstruction but are neither universally present nor specific to asphyxia.
The independent assessment
Pathologists retained by Floyd’s family, including Dr. Michael Baden, announced on June 1, 2020, that Floyd had died from “asphyxia due to neck and back compression.”
One limitation was that this conclusion was announced before the pathologists had reviewed the complete toxicology findings. According to contemporaneous reporting, they did not yet have information about possible drug or alcohol use. Their assessment therefore did not initially account for the fentanyl, methamphetamine, or complete cardiovascular findings.
A forensic cause-of-death opinion should integrate the autopsy, toxicology, medical history, scene investigation, and circumstances of death. An assessment issued before all those elements are available should be regarded as preliminary.
Interpreting the complete record
The evidence supports several carefully bounded conclusions.
The autopsy did not document a crushed airway, traumatic neck injury, or another specific anatomic finding that independently established fatal asphyxia. Floyd’s speech shows that his airway was not completely obstructed while he was talking. Toxicology identified fentanyl at a concentration reported in fatal overdoses, while the autopsy documented severe cardiovascular disease and methamphetamine exposure.
None of these findings, alone or together, proves that the restraint did not contribute to death. Conversely, the circumstances of the restraint do not eliminate the need to evaluate the toxicology, underlying disease, and absence of traumatic findings.
The central diagnostic issue is therefore not a simple choice between restraint and overdose. It is how multiple potential contributors combined to produce cardiopulmonary arrest and whether the available evidence can identify a specific physiological mechanism with confidence.
The later memoranda and meeting minutes show that similar questions existed among professionals involved in the case. They do not conclusively demonstrate that the final certification was wrong or improperly influenced. They do, however, illustrate the importance of distinguishing documented findings from inference – and of communicating uncertainty when the autopsy, toxicology, and scene evidence permit more than one interpretation.
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