Two autopsy results — one requested by George Floyd's family and the other from Hennepin County — agree that his death is a homicide but disagree over exactly what killed him.

During a news conference Monday afternoon, two doctors hired by the Floyd family to do a private autopsy said they believe he died of asphyxia, which happens when oxygen flow is cut off, causing the brain and other organs to stop working.

"We believe truth will help lead to justice and so, despite how painful these autopsy findings are, especially for George Floyd's family, we think it is essential that the truth comes out about the manner and the exact manner and science as to how George Floyd was killed," Benjamin Crump, an attorney for the Floyd family, told reporters.

Hours later, the Hennepin County Medical Examiner's Office issued its final public report, stating that Floyd died as a result of "cardiopulmonary arrest complicating law enforcement subdual, restraint, and neck compression." A spokesperson for the office, citing Minnesota laws, said they could not discuss that cause of death further.

The report noted that Floyd "experienced a cardiopulmonary arrest while being restrained by law enforcement officer(s)."

It also listed "arteriosclerotic and hypertensive heart disease," as well as fentanyl intoxication and recent methamphetamine use as "other significant conditions."

It was the most extensive description released yet of the autopsy performed by the Medical Examiner's Office on the 46-year-old Floyd, who died on May 25 after his curbside detention at E. 38th Street and S. Chicago Avenue by officers who suspected him of passing fake currency at a store.

Derek Chauvin, who was seen on video pinning his knee on Floyd's neck, was fired from the force and has been charged with third-degree murder (up to 25 years in prison) and second-degree manslaughter (up to 10 years in prison).

Three other officers who were present were also fired but had not been charged as of Monday evening.

It is too early to tell exactly what significance, if any, the differing findings could play in Chauvin's case.

"I don't even know how this goes," said Bradford Colbert, a practitioner in residence at Mitchell Hamline School of Law. "It's not exactly clear to me, because in a criminal case, it's the state vs. the defendant. Theoretically, the victim does not have the right to be involved. That's how it rolls."

Either a prosecutor or a defense attorney could choose to enter the results of the family's autopsy into evidence at a criminal trial, but neither would be required to do so, Colbert said.

The results could also be used in a civil trial, if Floyd's family decides to sue.

Little has been publicly released about how the Hennepin County Medical Examiner's Office came to its conclusion on Floyd's cause of death.

In a criminal complaint supporting the charges against Chauvin, investigators wrote that "the autopsy revealed no physical findings that support a diagnosis of traumatic asphyxia or strangulation."

It also noted there were "underlying health conditions, including coronary artery disease and hypertensive heart disease."

While attorneys and doctors hired by the Floyd family did not release their written autopsy reports, saying they were still awaiting some additional results, they did describe their findings in some detail.

To come to their conclusions, they said they viewed the public videos of Floyd being pinned by Chauvin, as well as a report put together by EMT staff who worked on Floyd and examined the parts of his body to which they had access.

"The compressive pressure of the neck and back are not seen at autopsy because the pressure has been released by the time the body comes to the medical examiner's office," said Dr. Michael Baden, a forensic pathologist who performed an autopsy on behalf of the Floyd family.

"It can only be seen — serious compressive pressure on the neck and back can only be seen while the pressure is being applied or when, as in this instance, it is captured on video."

Baden said he believes that while Floyd was officially pronounced dead later, he actually died "after about 4 or 5 minutes."

Court documents filed in Chauvin's case say Floyd was pulled out of a squad car at 8:19:38 p.m., stopped moving at 8:24:24 p.m. and at 8:25:31 p.m., video "appears to show Mr. Floyd ceasing to breathe or speak."

Crump, the Floyd family attorney, said an EMT report they obtained shows that medics "performed pulse check several times, finding none, and delivered one shock … but George's condition did not change. They delivered him to the hospital, continued ventilation, but that last report was the patient was still pulseless. The ambulance was the hearse."

Baden said that they found "rough abrasions" on Floyd's left eye and left cheek "and a little bit in the front, on the nose and mouth areas." He said they also found "scrape marks on the back side of his left shoulder."

Preliminary findings released through the attorneys later in the day indicated that the doctors also found a hemorrhage "over the vertebral bodies and in the cervical region," as well as on the outside of the carotid artery and in the wrists and forearms.

"The cause of death, in my opinion, is asphyxia due to compression of the neck," Baden said.

Baden and his colleague, Dr. Allecia Wilson, disputed the medical examiner's findings of heart disease — with Baden going so far as to say, "I wish I had the same coronary arteries that Mr. Floyd had that we saw at the autopsy."

Wilson noted that second autopsies have some limitations.

"Certain parts of the organs have been retained by the original pathologist," she said, though she didn't note which ones.

In their public statements, the Floyd family's attorneys and doctors said they believe that pressures on both his neck and his back caused Floyd's death. Paperwork filed in Chauvin's case indicates that officer J. Alexander Kueng "held Mr. Floyd's back" and officer Thomas Lane "held his legs." A fourth officer, Tou Thao, was seen on video standing nearby while Chauvin's knee was on Floyd's neck.

Attorneys for the four fired officers either declined to speak about the family's autopsy findings or were unavailable to comment.

Attorneys for the Floyd family welcomed the appointment of Attorney General Keith Ellison to prosecute the case and said they hope he will consider a first-degree murder charge for Chauvin. Co-counsel Antonio Romanucci called for charges for the other officers as well. Not only was Chauvin's knee on Floyd's neck, Romanucci said, "but so was the weight of the other two police officers on his back. … That makes all of those officers on scene criminally liable and, without a doubt, civilly responsible."

Liz Navratil • 612-673-4994

Paul Walsh • 612-968-2483