Noah Presgrove’s autopsy provides clues to his cause of death

Despite all the unanswered questions surrounding the death of Noah Presgrove, everyone agrees on one thing: the 19-year-old’s naked body had severe injuries when it was found on the side of the road on September 4.

Noah’s autopsy, obtained by PEOPLE in May, reveals the extent of blunt force trauma that led to his death, including severe head and skull injuries — the middle base of his skull was split in half — as well as life-threatening fractures of his vertebrae and more.

However, the official cause of death remains “undetermined.”

According to emergency calls, Noah’s body was found shortly before 6 a.m. local time on Labor Day 2023 along Highway 81, just a few miles outside of Terral in southern Oklahoma.

He was naked except for a pair of mismatched shoes, his autopsy states. Nearby was a pair of printed white shorts that showed no “visible damage,” along with “three pieces of a white metal chain as well as part of a tooth lying several feet away.”

(The necklace — one of Noah’s favorites — was never fully recovered, a first responder tells PEOPLE.)

According to the autopsy, a “tuft of hair” was found on his body; another tuft was found nearby. However, vehicle debris was not found, the autopsy states.

According to the emergency calls, the teenager was first spotted by two passing motorists. State authorities are still investigating – and almost a year later, his family is also looking for answers.

Investigators stated that the perpetrator’s death was not a murder, but declined to comment further, citing ongoing work.

Outside experts say the detailed findings of the coroner’s report provide some clues as to how Noah died, while also showing how difficult it may be to solve the central mysteries.

“The problem with this case is that so much is unknown,” Dr. Priya Banerjee, a board-certified forensic pathologist, tells PEOPLE.

Banerjee has nothing to do with the investigation but reviewed the autopsy and explained her views in an interview.

“Whatever caused these injuries, it was a lot of violence,” she says. “You don’t get a fractured skull, a fractured vertebrae, a fractured rib, all that bleeding without a lot of force being used on the body. I think the problem is that this could all be consistent with a hit-and-run, possibly some dragging, but I can’t really rule out that some of it was from a fight.”

Banerjee says that according to the autopsy, Noah appears to have been hit primarily on the left side of his head. “There was significant force exerted, resulting in a fracture of the base of his skull,” she says, also noting bleeding around and inside his brain.

She sees a large wound on the top left of his head – an abrasion that is described in the autopsy as an abrasion. “That’s where his scalp is basically torn off and lifted off his skull,” says Banerjee.

But “it’s a weird place that’s hard to get to, the top of the head is hard to get to,” she explains. “You don’t just fall backwards and hurt yourself there. Something happened where a force hit him or where he hit something.”

According to Noah’s autopsy, the wound was approximately 8 inches in diameter and exposed bone; there were also abrasions or cuts on his left eyebrow, left eye, and left cheek, as well as on his left ear, the left side of his neck, and the left side of his tongue.

Although some of those first on the scene, including Jefferson County Sheriff Jeremie Wilson, told PEOPLE they did not see as much blood as might have been expected given Noah’s injuries, Banerjee points out that Noah’s injuries to his neck and skull “would mean a quick death and therefore would cause little bleeding.”

Banerjee highlights injuries on his body that resemble abrasions on his back, as well as abrasions (or scratches) on his shoulders, buttocks, arms and legs.

“Was he hit by a car and dragged along a bit?” she says. “Possibly.”

He suffered “severe injuries” to his upper body and head, while his arms and legs suffered less injuries, Banerjee said, citing the autopsy: “He has severe bleeding in his chest. Both shoulder blades are broken, he has many broken ribs, left and right. His spine is broken in several places and he has bleeding on the sides of his chest and around his heart. Both lungs are punctured.”

Banerjee also points out that according to the autopsy, nothing was present, such as “no vehicle parts or debris.”

“If it was a hit-and-run, there should be car parts like a broken taillight or headlight. … That’s not necessarily the case, but there’s usually some debris,” Banerjee says. “When someone is left on the side of the road, we usually think of hit-and-run. But there’s also a concern that someone was left behind.”

Forensic pathologists are not allowed to examine themselves; that is the job of the police.

“I can’t look at the injuries and say I know exactly how they occurred, so it’s a mystery,” Banerjee said. “Was it a car accident, hit and run? Was it a deliberate collision with a vehicle? Did someone hit him and drop him? There are so many possibilities, and nothing about the pattern of injuries will help narrow it down any further.”

Some important details have been publicly confirmed, including that Noah was partying with friends on Labor Day weekend before his death, not far from the spot on Highway 81 where his body was found.

According to Noah’s autopsy, he rolled over while riding an ATV during the party on September 3, but then returned to the party where an argument broke out and he left.

“I don’t think the serious injuries that led to his death were related to the ATV, because we know he was alive and returned to the party. Could he have bumps, scratches or bruises? Sure,” Banerjee says. “And then – did someone push him out of a car or run him over? I just don’t know. Was there a road accident after that? Probably.”

The information about Noah’s injuries answers some, but not all, questions. “These are the cases that are gray. They are not black and white,” says Banerjee.

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Noah’s best friend, Jack Newton, was with him at the party that weekend. Jack tells PEOPLE that around 3 a.m. on Sept. 4, Noah and a few others were riding Jack’s ATV — while Jack was sleeping — and while Noah was driving, “it just tipped over on its side.”

No one was seriously injured, Jack says, and Noah showered and then left at 3:30 a.m., less than three hours before he was found dead.

But Jack also says that he was told this later because he was supposedly sleeping. Different reports contradict each other.

“Everyone I’ve asked will tell you a different story,” he says of one of the details, namely Noah’s cleanup after the ATV incident.

Everett Baxter Jr., a forensic scientist and former Oklahoma police officer, agrees with Banerjee that Noah probably did not sustain his serious injuries, such as the fractured vertebrae, on the ATV.

“If that had happened during the crash … he would have been dead. He wouldn’t have moved,” Baxter says.

At the same time, Baxter, who, like Banerjee, has nothing to do with the case but examined the autopsy as an expert, suspects that Noah may have suffered a head injury on the ATV that affected his behavior and demeanor.

Still, the way Noah’s body was found is so strange: “You have to go back and answer the question: Why was he naked?” says Baxter.

“Did the clothes come off because he took them off, or did they come off because someone else took them off?” he says.

Police said they are continuing to investigate what actually happened to the teenager.

But Baxter feels that “some people don’t disclose all the information.”

“It’s common in this part of the state,” he says, referring to the rural communities along the Oklahoma-Texas border that follows the meanders of the Red River.

“People in this part of the state don’t share information freely,” he says.