Chad Daybell, a murder suspect accused with his wife, Lori Vallow, of killing Vallow's two children and collecting their social security benefits in 2019, is asking for his trial to be delayed and separated from his wife's. 

The pair at the center of the bizarre murder case involving not only Vallow's two children but both Daybell's and Vallow's deceased ex-spouses were scheduled to appear in court together on Jan. 9 for a joint trial, but now, Daybell is making efforts to sever their cases, according to Tuesday court filings in Fremont County, Idaho.

Daybell initially filed a motion to separate his case from his wife's in 2021, which the court denied in March citing three potential sources for prejudice. The murder suspect's lawyers argued that the court's reasoning was an incorrect application of Idaho law.

"Mr. Daybell moves to sever his trial from that of his co-defendant based on the change in circumstances over the [10] months since he last moved to sever and due to the previous application of an improper legal standard," his counsel wrote in their motion to sever filed Tuesday. 

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Lori Vallow and Chad Daybell

Lori Vallow and her husband, Chad Daybell, are facing murder charges in the deaths of Vallow's two children and their former spouses. (The Associated Press)

His attorneys noted that prosecutors are seeking the death penalty in Vallow's case if she is convicted and argue that a joint trial "would violate Mr. Daybell’s rights to present complete defense, to fair and reliable merits phase determination, to an individualized sentencing determination, to confrontation of witnesses, and to due process pursuant to the state and federal constitutions."

In other words, his attorneys are arguing that a joint trial is unfair in this case because prosecutors are seeking the death penalty for Vallow, which may result in prejudice against Daybell. Additionally, his lawyers state that the defendant will not be able to present a "complete defense" in a joint trial, among other conflicts.

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Daybell's counsel is also asking for his trial date to be pushed back from January 2023 "due to the substantial amount of trial investigation and preparation and significant amount of discovery" that they say has still not been provided to the defense by prosecutors.

Chad Daybell booking photo

Lori Vallow and Chad Daybell are at the center of a tangled case that involves a bizarre apocalyptic religious belief that prosecutors claim the couple designed to justify the murders. (Rexburg Police Department)

"Death penalty cases are unique in the criminal legal system and require counsel to undertake an extensive, time—consuming investigation for essentially two trials: the merits phase and the sentencing phase in the event there is conviction," Daybell's motion to continue filed in Fremont County on Tuesday states. "… Due to the complexity of the merits case, which has dominated undersigned counsel’s time, the sentencing phase investigation is in its initial stages. Moreover, there are substantial outstanding issues which must be litigated prior to trial."

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Finally, Daybell is asking for a "bill of particulars" in the murder case, which would detail his "specific acts with which he is charged." His attorneys argue that the initial indictment is too vague.

Chad Daybell and his attorney in court

Daybell and Vallow were indicted in late May 2021 on multiple counts each of conspiracy to commit first-degree murder and grand theft by deception, first-degree murder and conspiracy to commit first-degree murder related to the deaths of Tylee; J.J.; and Chad Daybell's ex-wife, officials announced at the time. (Post Register/ John Roark, POOL)

Vallow's two children, 7-year-old Joshua "J.J." Vallow and 17-year-old Tylee Ryan, were killed in September 2019. Vallow and Daybell have been accused of collecting Social Security benefits with their information between Oct. 1, 2019, and Jan. 22, 2020. 

The children were missing for several months — when police say the couple lied about the children’s whereabouts and then slipped away to Hawaii — before their bodies were found buried on Chad Daybell's property in rural Idaho.

Joshua Vallow, 7, and Tylee Ryan, 17, are being sought by police in Rexberg, Idaho. Investigators are saying their mother, Lori Daybell, knows what happened to them but refuses to cooperate.

Lori and Chad Daybell are accused of killing 17-year-old Tylee Ryan and 7-year-old J.J. Vallow in 2019. (Rexberg Police Department)

The couple was indicted in late May 2021 on multiple counts each of conspiracy to commit first-degree murder and grand theft by deception, first-degree murder and conspiracy to commit first-degree murder related to the deaths of Tylee; J.J.; and Chad Daybell's ex-wife, officials announced at the time. Arizona officials in June 2021 also indicted Vallow in the July 2019 murder of her ex-husband, Charles Vallow.

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The case has garnered national attention and inspired various crime television episodes, documentaries and so on. Netflix most recently released the documentary series "Sins of our Mother" about Vallow and her life before the alleged crimes on Sept. 14.

Daybell has written several apocalyptic novels based loosely on Mormon theology. Both were involved in a group that promotes preparedness for the biblical end times. Meanwhile, Vallow reportedly believed she was "a god assigned to carry out the work of the 144,000 at Christ’s second coming in July 2020," according to divorce documents that her late ex-husband, Charles Vallow, filed before his death.