Source: John Dale Dunn, MD, JD

On July 29, District Court Judge Peter Cahill, the presiding judge in the trials of the four Minneapolis police officers indicted for the death of George Floyd, ordered the release of an exhibit memorandum that reveals a miscarriage of justice and criminal coercion of a witness.

Dr. Roger Mitchell, the former deputy mayor and medical examiner of the District of Columbia and now the Chief of Pathology at Howard University Medical School, a traditional Black medical school, boldly intimidated and coerced Hennepin County Medical Examiner Dr. Andrew Baker into changing critical conclusory language in his autopsy report on the death of George Floyd.

The exhibit is a written summary of Mitchell’s commentary and some admissions of coercion that he volunteered to Minnesota Attorney General Office prosecutors in November 2020.  Mitchell’s perfidious conduct is discussed in this excellent article by Jack Cashill.

Dr. Andrew Baker, an experienced and well-regarded Chief Medical Examiner for Hennepin County, conducted an autopsy on Mr. Floyd on May 26, 2020, the day after his death, and reported later that day, “The autopsy revealed no physical evidence suggesting that Mr. Floyd died of asphyxiation or that excessive force was used in the restraint performed by the officers led by Officer Chauvin.   

Three days later, on Friday, May 29, prosecutors elaborated on the cause of death in posting their initial complaint against Derek Chauvin. According to the complaint, “The full report of the [medical examiner] is pending but the [medical examiner] has made the following preliminary findings. The autopsy revealed no physical findings that support a diagnosis of traumatic asphyxia or strangulation.”

The autopsy did show, however, that Floyd had severe heart disease, coronary artery disease, and an enlarged heart from high blood pressure. These conditions put Mr. Floyd at risk for sudden death from cardiac arrhythmia — an abnormal ineffective lethal heartbeat.

Before you proceed, think about that: Baker’s initial clean impression, without corrupting pressures, was that Derek Chauvin and his fellow officers were in no way responsible for George Floyd’s death.

Without a diagnosis of asphyxia, the State could not prosecute the officers for murder.  That is why Dr. Roger Mitchell was so critical in this tale of intimidation — and why this exhibit memorandum is so important. It reveals a naked attempt by Roger Mitchell to bully Dr. Baker into a conclusion that would enable a second-degree murder prosecution of the police officers.

Don’t take my word for it. Here is how the Minnesota prosecutors summarized their meeting with Dr. Mitchell in the memorandum:

When the preliminary result came out via the criminal complaint, Mitchell found the statement was bizarre. Mitchell was reading and said this is not right. So Mitchell called Baker and said first of all Baker should fire his public information officer. Then Mitchell asked what happened, because Mitchell didn’t think it sounded like Baker’s words. Baker said that he didn’t think the neck compression played a part and that he didn’t find petechiae. Mitchell said but you know you cannot have petechiae and still have asphyxia and can still have neck compression.

This phone call likely took place on Friday, May 29. Mitchell had a restless weekend as he drafted an op-ed for the Washington Post. His next step was pure intimidation:

Mitchell was expecting to send the op-ed to the Washington Post on Monday afternoon so Mitchell called Baker first to let him know that he was going to be critical of Baker’s findings. In this conversation, Mitchell said, you don’t want to be the medical examiner who tells everyone they didn’t see what they saw. You don’t want to be the smartest person in the room and be wrong.

The Cashill article cited above explains how Baker appears to have yielded to the pressure. In his second call to Baker, Mitchell insisted “neck compression has to be in the diagnosis,” and Baker ultimately added “neck compression.” Without that addition, Chauvin could not have been charged with murder.

Not being a physician, Cashill asked me to assess Mitchell’s conduct and his review of Baker’s work. I answered Mr. Cashill’s questions because I can.  I am an attorney admitted to the bar in Nebraska, Louisiana, and Texas by examination and I have a career-long interest in studying causes of death, especially sudden causes of death. I have been an emergency physician since 1974, an attorney since 1979, and have co-authored with a pathologist a chapter on forensics for a textbook published by the American College of Legal Medicine: Legal Medicine: Legal Dynamics of Medical Encounters (Mosby, 1988 and 1991).

What follows is a bit long and technical. I am hoping that those involved with the defense of the four officers, close to the show trials will find my answers and commentary helpful.  My analysis of the Mitchell interview memorandum is in italics.

—Autopsy pretty complete but noted Baker did not perform a layered posterior neck dissection

Dunn response

 Of course, Baker dissected the neck. He could not have reached the following conclusions without it. These come from what I considered a fine and careful autopsy by Baker:

—No life-threatening injuries identified

—No facial, oral mucosal, or conjunctival petechiae

—No injuries of anterior muscles of neck or laryngeal structures

—No scalp soft tissue, skull, or brain injuries

—No chest wall soft tissue injuries, rib fractures (other than a single rib fracture from CPR), vertebral column injuries, or visceral injuries

—Incision and subcutaneous dissection of posterior and lateral neck, shoulders, back, flanks, and buttocks negative for occult trauma

Here are some further findings by Baker regarding Floyd’s neck:

Layer by layer dissection of the anterior strap muscles of the neck discloses no areas of contusion or hemorrhage within the musculature.

— The thyroid cartilage and hyoid bone are intact.  The larynx is lined by intact mucosa.  

—The thyroid is symmetric and red-brown, without cystic or nodular change.  

— The tongue is free of bite marks, hemorrhage, or other injuries.

—The cervical spinal column is palpably stable and free of hemorrhage.


Reviewed photos 122 and 123 pointed to a dark spot that could be a hemorrhage but was hard to tell without a layer posterior neck dissection.

Dunn response

This is nothing more than another bruise that showed up on the pictures of the body—multiple abrasions and bruises of a superficial nature present were the product of the resisting arrest scenario, and Mitchell knew that. Mitchell ignored the dissection of the neck, shoulders, back, flanks and buttocks by Baker that showed no evidence of trauma.

It appears that Dr. Mitchell didn’t even read the draft version of the autopsy.


The lack of a hemorrhage in the deep tissue doesn’t necessarily add value but the presents (sic) of a hemorrhage can be helpful to understand the amount of pressure

Dunn response 

No sign of injury exonerates the officers and works against Mitchell’s agenda of police abuse and asphyxiation—he wants to cherry-pick his evidence.


George Floyd had an open airway but goes into cardiac arrest while the knee is on his neck. Mitchell agrees with Baker that the neck compression is a component of the mechanism of death.

—Mitchell evaluated the various potential impacts of the compression of the neck and noted they include possibly causing an arrhythmia (sic), he also said it can imped (sic) blood flow to the brain, vaso vagal response
—Mitchell discussed struggle and impact on heart
—The sooner he gets care the higher likelihood he will live
—At no point are they issuing life support care
·—You can feel yourself dying, you have to move. He was in crisis – physical crisis
—The actions of law enforcement were preceded (sic) cardiac arrest
—Regarding the cause of the cardiac event, Mitchell believed the effect on circulation was potentially more significant than the impeded ventilation. However, Mitchell was somewhat unsure because he also believed the neck
compression played a significant part in Floyd’s death

Dunn response

Here Mitchell goes in circles. He admits that the manner of death was more likely cardiac and circulatory, but he then reasserts his opinion that neck compression impeded ventilation, but then he also speculates that it may have impacted circulation.

—All the while he knew that the neck showed no signs of injury at autopsy.

—Moreover, Mitchell ignores the critical information on the brain tissue exam that shows no evidence of lack of oxygen (hypoxia):


Sections of hippocampus, cerebellum, cerebral cortex, and midbrain show the expected microscopic architecture, without hypoxic– ischemic, reactive, neoplastic, or inflammatory changes.


—With respect to the term Asphyxia (sic), there are typical indicators of asphyxia that are not present but also believes the neck compression played a significant part in Floyd’s death.
—Neck compression can comprise (sic) blood delivery into the brain and can cause hypoxia.
—Baker’s lack of use of the term asphyxia is a style issue.

Dunn response

Stop the presses! Style issue? No, it isn’t a style issue—it has to do with a proper cause of death analysis and conclusions. Baker found no evidence of petechiae which is the most common diagnostic change caused by asphyxiation, the autopsy found no crushing injury of the neck and no hypoxic brain injury


—Did not die from overdoes (sic)

—Fentanyl is an opioid, which does compromise respiratory drive. But Floyd, when the officers first encounter him, is not having trouble breathing.
—Mitchell does not believe that the Fentanyl or any of the drugs in his system are playing a part in Floyd’s death

—In order for these drugs to cause death, the user would be in a stupor, brainstem no longer functioning properly and dying from the fact that brainstem is suggesting you have enough oxygen and you are holding on to carbon dioxide

Dunn response

 Yes indeed, this was not a Fentanyl overdose—which causes lethargy, stupor, and respiratory failure/arrest. However, Mitchell ignores the cardiac arrhythmia risks created by heart disease, agitation, and methamphetamine.


—Lungs = normal
—Heart = not normal
—High blood pressure
—Dilated heart
—Cardiovascular disease puts Floyd at risk for fatal arrhythmia

—Cardiac arrhythmia was a risk because of Mr. Floyd’s bad heart disease

Dunn response

Mitchell makes the case for cardiac arrhythmia, so why is he pushing Baker on neck compression?  Simple, he had a political anti-police agenda.  Mitchell read what he wanted to read and ignored the evidence that was right in front of him. He had a racially motivated tunnel vision. Police misconduct killed Mr. Floyd—now let’s figure out how.

Mitchell ignored the evidence that showed the most likely cause was a bad heart, the physical exertion of resistance, and agitated intoxication combined with methamphetamine that caused fatal cardiac arrhythmia, just what forensic pathologists see all the time, cardiac arrest during exertion.

In June, I wrote an article explaining how the prone position is not lethal or harmful. I backed up my assertion with an experiment/demonstration on video of the prone position restraint applied for 10 minutes just as Chauvin did to George Floyd. The individual on top applying the restraint weighed 170 pounds, and the individual playing the role of Floyd weighed 230 pounds. The individual being restrained suffered no compromise of breathing or oxygen level and certainly no risk to health.

The futures, perhaps even the lives, of police officers are at stake.  Fraud or deception by a witness or coercion of fraudulent evidence or testimony under oath is criminally actionable and certainly can be grounds for a mistrial.  Allowing critically important evidence and testimony to be silenced enables a miscarriage of justice. Officer Chauvin did not murder Mr. Floyd.