Trial of Lori Vallow Daybell, Idaho mother accused of killing her children, begins Monday: Here's what to know

In a murder case that has both captivated the nation, the trial of Lori Vallow Daybell, the Idaho woman accused of killing her two youngest children and her husband's ex-wife nearly three years ago, is set to begin.

Jury selection is scheduled to start Monday, in a trial that has already been postponed twice for several reasons, including testing Daybell's competency. This surreal saga has drawn widespread speculation and has even been the subject of a Netflix docuseries.

VallDaybell and her husband, Chad Daybell, have pleaded not guilty to a litany of charges including murder, conspiracy, and grand theft in the 2020 deaths of Joshua "JJ" Vallow, 7, and Tylee Ryan, 16.

The couple is also accused of killing Chad Daybell's previous wife, Tammy Daybell, who unexpectedly died in October 2019, about two weeks before Chad Daybell married Vallow Daybell.

Prosecutors say that Vallow Daybell and Chad Daybell practiced apocalyptic and doomsday-driven religious beliefs as part of a plan to kill the kids and Tammy Daybell. Prosecutors also allege the strategy was part of a plot to steal social security funds and insurance money.

A trial date has not been set for Chad Daybell, as a judge separated his case from Vallow Daybell after new evidence was submitted regarding DNA testing. The Daybells could face life in prison or, in the case of Chad Daybell, also the death penalty, if convicted.

"This trial is definitely going to be a show for sure, and even more so if Lori (Vallow Daybell) takes the stand," said John Delatorre, a forensic and disaster psychologist in Arizona and Texas. "I’m interested to see the evidence the prosecution is going to negate the delusional thinking that Lori has engaged in."

Vallow Daybell's sordid, twisted tale

Police in Idaho began investigating Vallow Daybell and her husband after JJ's grandmother and other family members said they hadn't heard from their two grandchildren in months and reported them missing in November 2019.

Police later said the kids were last seen in Rexburg, Idaho, on Sept. 23, 2019. The couple refused to cooperate with the investigation and soon left Idaho and fled to Hawaii in December 2019. The couple also announced the children were missing and potentially in danger.

Police said that Vallow Daybell knew where the children were. Authorities would begin a search for the couple and order them to produce the children. The couple was found in Kaua'i, Hawaii, in January 2020, without the kids. The couple was extradited to Idaho.

The children's bodies were later found buried on Daybell's property in rural eastern Idaho in June 2020.

"We are filled with unfathomable sadness that these two bright stars were stolen from us and only hope that they died without pain or suffering," said a statement attributed to JJ's biological grandparents, Larry and Kay Woodcock, the East Idaho News reported.

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Prosecutors: Vallow Daybell, husband held spiritual beliefs involving 'zombies' and doomsday predictions

The couple promoted strange religious beliefs, prosecutors say. Friends also told law enforcement investigators that Vallow Daybell and Chad Daybell believed people could be taken over by dark spirits.

At one point, a friend of the couple, Melanie Gibb, told investigators that Vallow Daybell referred to her children as "zombies," a term the couple allegedly used to describe people who were possessed.

Prosecutors have argued that the couple adopted apocalyptical beliefs to encourage or justify their murders.

Vallow Daybell's trial was first postponed in 2021 after she was declared incompetent to stand trial. She was committed to the Idaho Department of Health and Welfare for treatment.

About 10 months later, Vallow Daybell was ruled competent after a second trial was postponed to await results to determine if she was mentally fit for trial.

Now that the trial is set to begin, Vallow Daybell's legal team requested that the judge exclude most family members from watching portions of her trial, according to KTVB-TV.

Vallow Daybell's defense attorney Jim Archibald specifically pointed out that Kay Woodcock, JJ Vallow's grandmother, is expected to attend the trial and could be called to testify.

Archibald argues that Woodcock is "not a grandma," and doesn't fall into Idaho state code that any immediate family is considered victims of homicides, the TV station reported.

"(Grandma) is a name she gave herself," Archibald told District Court Judge Boyce about Woodcock. "Her son terminated parental rights, she's not a grandma."

But prosecutors claim Woodcock and her husband meet the state's definition of immediate family members.

Boyce has already issued an order to exclude witnesses from sitting in on others' testimony to potentially prevent problems. The judge also will issue a ruling on the immediate family matter soon.

Vallow Daybell won't face the death penalty

Vallow Daybell will not face the death penalty if she is convicted at trial, Boyce ruled last month.

Prosecutors were seeking the death penalty for Vallow Daybell and her husband, Chad Daybell.Vallow Daybell's lawyers argued that they didn't have enough time to go over the prosecution's recently submitted evidence.

The judge agreed, according to the Associated Press. The judge said Vallow Daybell has not waived her right to a speedy trial, so the proceeding could not be rescheduled to give her defense team enough time to review the new evidence.

The death penalty still applies to Chad Daybell’s case.

And that death penalty application may make a difference for Chad Daybell if prosecutors could strike a deal with him in exchange for a possibly lesser sentence if convicted, Delatorre, the forensic psychologist said.

A potential deal might even include Daybell testifying against his wife, Delatorre added.

"I would not be surprised if he takes the stand. I don’t think Chad is as devout of a believer as Lori is," Delatorre said. "If he decides to be a witness for the prosecution, it may be from the perspective of 'How can I make this all better for me?'"

And then there's the possibility that Vallow Daybell might have to testify in her defense if her husband testifies against her, Delatorre said.

"Some jurors may have a hard time believing a mother is capable of killing her children, Delatorre said. "The first assumption is women can’t do that; And the second is if she did it, it was because she was crazy.

"And those theories are not where the prosecution wants the jury to go," Delatorre concluded.

Delatorre said all it takes for the defense is for one juror to have a reasonable doubt Vallow Daybell didn't commit the crimes.

"I think it is a double edge sword to Vallow Daybell to testify," Delatorre said. "There's a lot of high-risk, high reward."

Firing line: Idaho lawmakers approve bill that could allow firing squad executions

More legal problems

Vallow Daybell also faces conspiracy to commit murder charges in Arizona in connection with the death of her previous husband Charles Vallow.

Charles Vallow was fatally shot in 2019 by Vallow Daybell's brother Alex Cox. Both Vallow Daybell and Cox claim the shooting was in self-defense.

Cox later died of what police say were from natural causes.

The Arizona case remains on hold as Vallow Daybell's fate in the Idaho trial unfolds.

This article originally appeared on USA TODAY: Trial of Lori Vallow Daybell, mom accused of killing her kids, begins