Brian Laundrie's notebook confession: Experts weigh in on killer's claims about how he murdered Gabby Petito

NORTH PORT, Fla. - Brian Laundrie framed his strangulation of Gabby Petito as an act of mercy and an "unexpected tragedy" in a handwritten confession discovered near his remains in October and just unveiled Friday. Experts moved quick to dissect his story.

Gabby Petito murder: Brian Laundrie’s notebook confession revealed, 'I ended her life'

Laundrie claimed she was "violently shaking," "freezing cold" and had apparent injuries before he killed her and set off down a path toward his own suicide.

Longtime medical examiners doctors Michael Baden, Cyril Wecht and Brent Blue – the latter of whom performed the autopsy on Petito, 22, in late 2021, spoke to Fox News Digital Friday just hours after details from Laundrie’s confession were released. So did John Kelly, a criminal profiler and psychotherapist who has interviewed numerous killers, and Jason Jensen, a private investigator. Laundrie, 23, scrawled eight notebook-pages of notes that he left behind before allegedly shooting and killing himself in a Florida environmental park.

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Fox News Digital was first to report the details of the note. Laundrie wrote how he "ended her life" because he "thought it was merciful, that it is what she wanted."

"He tiptoed around the confession. He wanted to serve it up as a mercy killing," Kelly told Fox News Digital. "That’s the thing that is bugging me more than anything."

Laundrie claimed he and Petito were "trying to cross" a stream when he heard "a splash and a scream." 

"I couldn’t find her for a moment, shouted her name. I found her breathing heavily gasping my name, she was freezing cold," he wrote. "When I pulled Gabby out of the water she couldn’t tell me what hurt. She had a small bump on her forehead that eventually got larger. Her feet hurt, her wrist hurt but she was freezing, shaking violently, while carrying her she continually made sounds of pain, laying next to her she said little lapsing between violent shakes, gasping in pain, begging for an end to her pain."

SEE IMAGES OF THE NOTE LEFT BEHIND:

Laundrie added: "I don’t know the extent of Gabby’s injurys (sic). Only that she was in extreme pain."

Kelly scoffed at this version of events: "He found her breathing heavily and gasping for breath, so he decided to choke her out? An ‘unexpected tragedy’ is when you get in a car accident or you slip and fall and God forbid someone gets hurt really bad."

Dr.  Blue, Wyoming’s Teton County Coroner, ruled Petito’s death a homicide as a result of manual strangulation and blunt-force trauma to the head and neck. He told Fox News Digital on Friday he was limited in what he could discuss about the case.

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"According to Wyoming Law, all I can release is her name, her birthday and her cause and manner of death," he said, when reached by phone. The coroner’s office did not release Petito’s autopsy report.

READ A TYPED VERSION OF THE NOTE HERE:

Jenn Bethune, who was in the area of Wyoming at the time of Petito's death, disputed Laundrie's claims regarding the temperature. Bethune told Fox News Digital the weather was around the high 40s, instead of the 38 degrees Fahrenheit that Laundrie claimed.

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Even if Petito had experienced hypothermia before her death, her remains likely would not have shown such signs, explained Dr. Wecht, who did not work on the case and is not barred from speaking on it. If her body had been hypothermic or had been exposed to such low temperatures for an extended period of time, a forensic pathologist would likely not be able to tell unless the condition was "severe and prolonged." 

Even then, Wecht told Fox News Digital, the length of time that passes before the body is recovered would also play a role. However, Wecht said violent shaking is not a sign of severe hypothermia.

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"Hypothermia, at the beginning, you'll be cold as hell ... But then when the hypothermia becomes significant, then you don't shiver, you don't move," he said. "In fact, in surgery, that's why they bring patients down into a hypothermic state. Everything slows down markedly."

Both Kelly and Jensen also found the story about Petito falling in the shallow creek hard to believe.

"He writes this farcical tale about her falling down and getting injured while crossing Spread Creek, and describes how he couldn't leave her behind," Jensen said, calling it "an attempt to rewrite history."

Laundrie did leave her behind, sometime in late August. Search teams found her remains on Sept. 19.

Laundrie's attempt to portray Petito's death as a mercy killing by strangling her on the spot instead of dragging her to the car and going for help makes no sense, Kelly said.

"I don’t believe in all this accident stuff because how can you say you love somebody so much, you can't go on without her, you love her so much you're willing to commit suicide like a Romeo and Juliet?" Kelly asked. "She's hurt, and you will not go and get help for her. And not only will you not go the extra mile, you will not even report her missing." 

Dr. Baden, who served as New York City’s chief medical examiner and has conducted more than 20,000 autopsies in his five-plus decades as a forensic pathologist, said there is some information, though not much, pointing to signs of stomach hemorrhaging as a result of severe hypothermia. 

"In general, hypothermia does not cause injuries that are easily found at autopsy. There is some information that there can be small hemorrhages in the stomach in the very severe cold depths," he explained. "But that's in the weeds. That's the weeds of forensic pathology."

He also had no attachment to the case.

If Petito had been concussed, as Laundrie claimed to have feared, such an injury would not have been evident during the autopsy examination, Baden and Wecht both said. 

"Nothing would be shown in the brain," Wecht said. 

However, if she had been, Kelly said that based on existing signs of domestic abuse, he believes it would have been intentional.

"If she had been hit on the head, it was by him," he said. "I don’t think this was an accident."

Wecht has been involved in some of the country’s most high-profile death investigations, including those involving President John F. Kennedy and JonBenét Ramsey. Baden has also been involved in high-profile cases, such as the death of financier and convicted sex offender Jeffrey Epstein.

"In any event, euthanasia is not legal in any state, anywhere," Wecht added. "Euthanasia is murder."

Aside from limited details released regarding the autopsy, Laundrie's handwritten confession also sheds lights on Gabby's last moments – and his homicidal logic. 

Patrick Reilly, an attorney representing Petito's family, told Fox News Digital outside the FBI building that he could not comment on Friday. The family's co-counsel, Richard Stafford, did not immediately provide a response. 

The Laundrie parents, for their part, felt "terrible" Friday, according to their attorney Steve Bertolino.

Even in his confession, a purported apology, he shirked responsibility.

"He stated he ended her life," Jensen noted. "He cannot admit ‘I killed her.’" 

Kelly said that the letter, along with Laundrie's past behavior on police body camera in Moab, Utah, and in a purported fight with wait staff at a Jackson restaurant shortly before Petito's death, exhibited signs of extremely narcissistic personality disorder and sociopathic disorder.

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Those events were also evidence of a pattern, according to Jensen.

"The truth is he killed her because he was a domestic abuser," Jensen said. "He strangled her and had done so before. The fact was suggested about their fight on Aug. 12 in Moab."  

Laundrie left her in the wilderness of Wyoming, alone, and drove home to Florida in her van and spending her money. Before he shot himself in the head in one of his favorite local parks, Laundrie went camping with his family, spent time with his nephews and ignored Petito's parents as they desperately sought information on her whereabouts. 

"The only thing I give him credit for, in a way, is he decided to get eaten up by animals himself," Kelly said. "In the end, it rang true he wanted to disappear. He felt he was a nobody."

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