A self-published author of novels about the last days, Daybell was convicted in 2024 of murdering his wife, Tammy Daybell, and Lori Vallow Daybell's two youngest children, JJ Vallow and Tylee Ryan. The jury sentenced him to death, and his appeal is pending before the Idaho Supreme Court.
Daybell's case is in the news again as his co-defendant's appeal reaches the Idaho Supreme Court. The court set oral argument in Lori Vallow Daybell's appeal of her 2023 convictions for Nov. 2, 2026.27 Daybell's own appeal and the court's automatic review of his death sentences have not been decided.21 Since August 2025, one of his daughters has posted letters she says he wrote on death row, in which he maintains his innocence.26
Daybell and his wife, Tammy, married in 1990, raised five children and moved to Salem, Idaho, near Rexburg, in 2015.23 In the fall of 2018 he met Lori Vallow at a religious conference in St. George, Utah.23 According to her appellate brief, which summarizes the record of her own trial, the two and others in their circle believed in prior lives, and Daybell taught that he could see “beyond the veil” and rate the light and darkness in people.3
In July 2019 Lori Vallow’s husband, Charles Vallow, was shot and killed in Arizona by her brother, Alex Cox, who told police it was self-defense and was not charged.103 On Sept. 1, 2019, she moved to Rexburg with her two youngest children, 16-year-old Tylee Ryan and 7-year-old Joshua “JJ” Vallow. Cox moved there too.3
Tylee Ryan was last photographed on Sept. 8, 2019, on a family trip to Yellowstone National Park.1625 JJ Vallow was last seen on the evening of Sept. 22, 2019, when, according to Lori Vallow Daybell’s brief, Cox carried him upstairs asleep; he did not return to school.316
At Daybell’s trial an FBI cellphone analyst testified that on the morning of Sept. 9, 2019, Cox’s phone was on Daybell’s property, in a spot “very similar” to where Tylee’s remains were later found, and that Daybell’s phone called Lori Vallow’s as Cox’s phone left. He testified that on the morning of Sept. 23, Daybell called Cox, Cox’s phone was then on Daybell’s property near where JJ’s body was found, and Daybell’s phone was in repeated contact with Lori Vallow’s. He cautioned that he was locating devices, not people.16
The children’s remains were found buried on Daybell’s property on June 9, 2020, and he was arrested that day.253 Prosecutors told the jury that Tylee’s DNA was found on two tools in Daybell’s shed.157 A forensic pathologist testified that JJ died of asphyxia, with a plastic bag and duct tape over his head, and that Tylee’s death was a homicide by means that could not be determined because of the condition of her remains.17
According to Lori Vallow Daybell’s brief, in early October 2019 a masked person fired what appeared to be a paint gun at Tammy Daybell in her driveway.3 She died at home on Oct. 19, 2019.12 Daybell told police she had been ill and died in her sleep; no autopsy was done, and she was buried in Utah within days.103 He and Lori Vallow married in Hawaii on Nov. 5.12
Her body was exhumed after Fremont County contacted the Utah medical examiner in December 2019. Utah’s chief medical examiner testified that she died of asphyxia, that the manner of death was homicide, and that bruises on her arms and chest were consistent with someone holding her down.18 A defense pathologist testified that the cause of death should have been listed as “undetermined,” and one of Daybell’s sons testified that he was home that night and heard no disturbance.10 Jurors heard that her life insurance had been increased before her death, and a former FBI agent testified that Daybell’s messages while she was alive showed that his greatest desire was to be with Lori Vallow.13
Prosecutors told the jury that Daybell and Lori Vallow, who were having an affair, wanted to remove obstacles to their relationship and to collect life insurance and the children’s survivor benefits.1410 They argued that the two promoted an apocalyptic belief system in which people could be possessed by evil spirits and become “zombies,” and that Daybell claimed to read a “death percentage” predicting who would die.1011 Prosecutors said Cox conspired in all three deaths.10 Cox died on Dec. 12, 2019; Lori Vallow Daybell’s brief says there is “no evidence that foul play was involved.” He was never charged in these deaths.37
Daybell pleaded not guilty.11 His lawyer, John Prior, described him as a devout Latter-day Saint whose beliefs were within the mainstream, and argued that Cox committed the killings and buried the children on Daybell’s property to frame him.1014 He told jurors no DNA from Daybell was found with the children’s remains.14 After the state rested, he argued there was no evidence Daybell was present when Tylee or JJ was killed. The judge found that the amended indictment’s date for JJ’s death was a clerical error and denied acquittal on all counts.13
Testimony began April 10, 2024, in Boise, where the case had been moved from Fremont County in 2021.1325 On May 30, 2024, after about six hours of deliberation, the jury convicted Daybell on all counts: first-degree murder and conspiracy to commit first-degree murder for each of the three victims, with grand theft by deception charged in the conspiracies involving the children, and two counts of insurance fraud tied to Tammy Daybell’s life insurance.10415
To impose death in Idaho, the jury must unanimously find at least one statutory aggravating circumstance beyond a reasonable doubt and decide, for each one, whether the mitigation is sufficiently compelling that death would be unjust.1 The state alleged that each murder was committed for remuneration and was especially heinous, atrocious or cruel, and also that Daybell showed utter disregard for human life and a propensity to commit murder.5 On June 1, 2024, the jury found that all the aggravating circumstances the state alleged existed, and that the mitigation was not sufficiently compelling to make death unjust. The four aggravators are listed in full below.48
Daybell chose to present no mitigating evidence. Asked repeatedly by Judge Steven Boyce whether he understood, he said, “That is my choice,” and he declined to make a statement.85 In argument, Prior described him as a “quiet, reserved and shy” young man whose life was changed by Lori Vallow, and argued that the case “had nothing to do with money.”5 The jury deliberated about six hours over two days.8 Boyce imposed death on all three murder counts and all three conspiracy counts and 15 years on each insurance fraud count, noting that Daybell had no prior criminal record and had conducted himself professionally in court.49
Prior filed a notice of appeal on June 3, 2024. It challenges the denial of his motion to dismiss the grand jury indictment, the exclusion of a defense doctor’s report and testimony, the amendment of the indictment after the state rested, the denial of the motion to dismiss, and the reasonable-doubt instruction given at both phases.19 Lawyers from the State Appellate Public Defender were appointed for the appeal and post-conviction proceedings.20 In August 2024 the judge found “extraordinary circumstances” and gave them more time, after they cited 16,800 pages of trial transcript and said they had learned of information just before trial that changed their approach to mitigation. The extension required the Idaho Supreme Court’s approval.22 The Idaho Supreme Court reviews every death sentence automatically.21 No decision had been reported as of Oct. 27, 2026.
Lori Vallow Daybell was tried separately after the cases were severed. A jury convicted her in 2023 of murdering Tylee and JJ and conspiring to murder Tammy Daybell, and she was sentenced to life in prison without parole.327 Her appeal is set for argument on Nov. 2, 2026.27
Daybell grew up in Springville, Utah, according to his trial lawyer, who described him at sentencing as a “quiet, reserved and shy” young man.285 He attended Brigham Young University, where he dug graves to pay his way.2423
Daybell worked on and off for almost 20 years as a cemetery sexton in Utah, in Springville and Spanish Fork.2324 He was a managing editor at a Utah publisher before founding his own, Spring Creek Book Company. He wrote more than 25 books, including Latter-day Saint-themed novels about the last days and a memoir of his work as a sexton.2324 Around the time he met Lori Vallow, the two recorded a podcast for a group called Preparing a People, which has since removed it and distanced itself from them.23
He and Tammy Daybell married in Manti, Utah, on March 9, 1990, and had five children. She worked as a school librarian in Idaho.23 Several of his adult children testified for the defense about their mother’s health, and they have said their father is innocent.11 After the sentence, a foundation in Tammy’s name thanked investigators, prosecutors and supporters.9
No mental health evaluation or diagnosis appears in the sources reviewed. Daybell presented no mitigation evidence at sentencing.8
Daybell has been in custody since June 2020 and on Idaho’s death row since June 2024.252 Since August 2025, one of his daughters has posted letters she says he wrote in prison. In them he writes, “I am not a conspirator or a killer,” says he still loves Tammy, and claims she was ill for months before she died, though several trial witnesses testified she showed no signs of illness.26
Prosecutors argued that Daybell and Lori Vallow Daybell, who were having an affair, killed to remove obstacles to their relationship and to collect life insurance and survivor benefits, and that they used apocalyptic religious beliefs to justify the killings.1014 They said Daybell was motivated by "money, power and sex."11
At trial his lawyer argued that the evidence did not tie Daybell to the killings, that Lori Vallow Daybell's brother Alex Cox was responsible, and that Tammy Daybell's cause of death could not be determined.715 Daybell has written from death row, "I am not a conspirator or a killer," and says he expects "a more complete story" to come out on appeal.26
Daybell and Lori Vallow meet at a religious conference in St. George, Utah.23
Tylee Ryan is last seen alive, on a family trip to Yellowstone.2516
Tammy Daybell dies at home; no autopsy is performed, and she is buried in Utah.123
Investigators find the children's remains on Daybell's property, and he is arrested.253
A Fremont County grand jury indicts Daybell and Lori Vallow Daybell on murder and conspiracy charges.253
Prosecutors announce they will seek the death penalty.25
Jury selection begins in Boise; opening statements follow on April 10.1325
His trial lawyer files a notice of appeal to the Idaho Supreme Court.19
The trial judge finds "extraordinary circumstances" and grants his appellate lawyers more time to prepare post-conviction claims.22
Letters attributed to Daybell, maintaining his innocence, are reported published online.26
The Idaho Supreme Court must review the death sentences; the review is mandatory, cannot be waived, and suspends the sentence while it is under way.21 In Idaho capital cases, post-conviction claims, such as ineffective assistance of counsel, are consolidated with the direct appeal.21 No ruling had been reported as of Oct. 27, 2026. Since July 1, 2026, Idaho law has made the firing squad its primary method of execution, with lethal injection as the backup.29