Chad Daybell trial: Medical examiner reveals Tammy Daybell’s death ruled a homicide by asphyxia

Utah Deputy Chief Medical Examiner Lily Mardsen was the state’s first witness on Tuesday in the case against Chad Daybell during his trial in Boise. Mardsen was working as a fellow at the medical examiner’s office when they were contacted by the Fremont Idaho County Law Enforcement regarding Daybell’s late wife, Tammy Daybell.

Chad Daybell is being accused of killing Tammy as well as Tylee Ryan, 16, and Joshua Jaxon “JJ” Vallow, 7. Tylee and JJ are the children of Lori Daybell, previously Lori Vallow, whom Chad married soon after the death of Tammy.

Lori Vallow was found guilty of two counts of first-degree murder and three counts of conspiracy in the deaths of Tylee, JJ and Tammy, last year. She was given five life sentences without the possibility of parole.

Mardsen was present during the exhumation of Tammy Daybell and worked alongside forensic pathologist Eric Christensen in the autopsy. She explained that “suspicious circumstances” was the reason for Tammy Daybell’s exhumation and there were specific procedures she and Christensen took during the autopsy.

After a thorough review, they found that Tammy Daybell had died from asphyxia, and her death was deemed a homicide. Asphyxia is what happens to the body when it is deprived of oxygen, resulting in unconsciousness or death.

Prosecutor Lindsey Blake asked if there was anything that caught her attention initially about the state of Daybell’s body, to which Mardsen said that she had bruises on her chest and arms. Mardsen also responded “yes” when Blake asked if the bruises could be consistent with someone being restrained or having pressure applied to them.

Mardsen said that she and her colleague tried to determine the time at which Daybell received those bruises.

“We took samples of the bruises to look at under the microscope, and when we did this, we’re looking for, you know, what causes the color of the bruise, which is hemorrhage or bleeding into the skin from the ruptured blood vessels. And then we’re looking at any type of inflammatory response the body is mounting to try to clean up all of the hemorrhage,” she said.

“All of the bruises on Ms. Daybell were what we would call acute,” she added. “Which meant that under the microscope, the only thing there was bleeding into the soft tissues under the skin,” meaning the body had not responded to try to “clean up the injury.”

She determined Tammy Daybell’s bruises to be “perimortem bruises,”meaning that they occurred a couple of hours before her death or possibly a few minutes after her death. She noted that the bruising could have possibly been by one or two people.

FBI’s location history of Alex Cox

The remainder of court time on Tuesday was filled with the testimony of FBI Special Investigator Rick Wright.

Wright said that the first time the FBI was notified by the Rexburg Police Department regarding JJ Vallow’s disappearance was on November 27, 2019. He added that he quickly became aware that JJ had an older sister but did not know she was missing at the time.

Soon after the call from the police department, they opened an investigation, and it became a classified kidnapping investigation.

In his testimony, he told the court that he used the location history of Alex Cox via cellular data during his investigation. Cox is the brother of Lori Daybell who died in December 2019 from natural causes.

On Monday, Blake showed the court satellite images of the Daybell property with data points showing Cox’s phone’s location. FBI agent Nick Ballance provided Wright with a file of Cox’s location history.

He said the investigation looked at Cox’s location on Sept. 8, 2019, in Yellowstone National Park. Wright said this was the last known location where they knew Tylee Ryan to be alive due to a photo taken of Tylee, JJ, and Alex that was shown to the court.

Wright discovered that Cox drove to and from Rexburg, Idaho, where he and Lori had apartments, and Salem, Idaho, where the Daybell property is, on multiple occasions.

Two dates in particular stood out — Sept. 9 and Sept. 23, 2019.

Wright said Cox’s phone was near Chad Daybell’s home in the early morning of Sept. 9, where Tylee’s remains were eventually found. And on the morning of Sept. 23, Cox’s location showed he was near the Daybell property again. That day happened to be the first day JJ was absent from school.

Blake asked Wright why the location points became more significant later on in the investigation to which he responded that they seemed to indicate the last time the children were known to be alive.

He also mentioned other locations that caught the investigator’s attention, including multiple trips to a variety of gun ranges and being near the Daybell property on Oct. 9, the day a masked person pointed a gun at Tammy Daybell.