Medical examiner says Alex Cox had blood clots in his lungs and died of natural causes

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GILBERT, Arizona — Alex Cox, Lori Vallow Daybell’s brother, had blood clots in his lungs, high blood pressure and died of natural causes. That’s according to a report released Friday from the Maricopa County Medical Examiner.

Cox, 51, was found unresponsive on his bathroom floor and pronounced dead at the hospital on Dec. 12, 2019. The medical examiner has been working on the case for months and on Friday released a seven-page report, along with a four-page toxicology summary, in relation to the investigation.

Maricopa County Medical Examiner Lesley Wallis said Cox died of bilateral pulmonary thromboemboli, meaning blood clots got wedged into an artery of his lungs. Wallis determined atherosclerotic and hypertensive cardiovascular disease, meaning plaque buildup in the arteries leading to high blood pressure, also contributed to his death.

What the report says

The medical examiner’s report shows detectives wrote Cox complained of shortness of breath and chest pain for about a week before being found unresponsive. On Dec. 12, he was found unconscious in his bathroom surrounded by feces, according to a 911 call obtained by First responders were called and rushed Cox to the hospital where he was pronounced dead.

Cox’s wife of two weeks, Zulema Pastenes, told investigators he had no prior medical history and did not take any regular medications, according to the report.

Cox weighed 227 pounds and was 6-foot-1. He appeared relatively healthy on the outside but when the medical examiner opened up Cox’s body, it was a different story, according to the report.

Inside Cox’s lungs were arteries clogged by blood clots and other arteries had a severe buildup of plaque, leading to high blood pressure. Wallis also found non-cancerous tumors inside his liver, an enlarged prostate and a polyp in the digestive tract.

The medical examiner performed extensive tests including a toxicology report, which showed caffeine and a drug called Narcan in his system. First responders give Narcan to non-responsive people to reverse the effects of an opioid overdose.

What could this mean

Dr. Burton Bentley II, an emergency physician and CEO of Elite Medical Experts in Arizona, told there are five options for a manner of death:

  • natural
  • suicide
  • homicide
  • accidental
  • undetermined

In the case of Cox, the medical examiner determined the death was due to natural causes.

“So they likely opened him up, they saw bilateral pulmonary thromboemboli (blood clots) and they had no other more probable cause of death,” Bentley said. “Likely the toxicology screens and things were negative and there was enough of an embolic effect (blood clots) as to make that the most probable cause.”

Bentley’s company is involved with thousands of cases around the world and realizes some may question how blood clots could have killed Cox.

“People who form clots usually have a reason,” Bentley said. “They’ve either had a prior clot, or they have a clotting disorder… or they have an acute attributing factor.”


Those factors could include prolonged periods of immobilization, such as those who had a recent surgery, a long airplane ride or a lengthy road trip, according to Bentley. He did say the blood clot killing Cox could not have happened at the hands of someone else.

“Homicide was not chosen as a manner of death,” Bentley said. “They are saying specifically this is not a homicide and this did not occur with the evidence that they have at this time. The objective evidence would, to a reasonable degree of medical probability, lead the medical examiner to conclude that this is natural.”

At the bottom of Cox’s medical exam report, Wallis included how the opinions “are amendable to change should new, reliable and pertinent information come to light.”

A spokeswoman with the Gilbert Police Department told Friday they were not prepared to comment but will soon.

Why such a deep look at Alex?

Alex Cox is Lori Vallow Daybell’s brother and admitted to shooting her estranged husband, Charles Vallow, in self-defense last July.

Months later Cox moved to Rexburg and rented a townhome in the same complex as Daybell and her two childern, 7- year-old Joshua “JJ” Vallow and 17-year-old Tylee Ryan. The children disappeared in September and Cox was seen in the last known photos of Tylee at Yellowstone National Park.

Surveillance video obtained by show him visiting a Rexburg storage facility in October with his sister and by himself several times. Video in November shows him opening a storage unit with Chad Daybell, Lori’s new husband.

Cox was never charged with any crimes but a private investigator believes he fired a shot at Brandon Boudreaux, the ex-husband of Lori Daybell’s niece, Melani Boudreaux.

Click here for complete coverage on the Daybell case.

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Eric Grossarth


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