WHEN A BELOVED COLLEGE STUDENT DIES WITH UNUSUAL BRUISING, HER PARENTS GO TO EXTREME LENGTHS TO PROVE HER DEATH WAS NO ACCIDENT

Peter Van Sant Reports in "For the Love of Cayley Mandadi"

Cayley Mandadi was a 19-year-old sophomore at Trinity University when she arrived at a hospital in Texas on Oct. 29, 2017. She was nearly naked, bruised and not breathing. Her sometime boyfriend Mark Howerton told doctors they'd taken ecstasy at a music festival and she passed out after consensual sex in his car. She died at the hospital. Mandadi's mother and stepfather believed something far more sinister had happened and set out to prove it. Peter Van Sant reports on the case in 48 HOURS: "For the Love of Cayley Mandadi," to be broadcast Saturday, Jan. 20 (10:00-11:00 PM, ET/PT) on the CBS Television Network and streaming on Paramount+.

The medical examiner ruled Mandadi died of blunt force trauma to the head and face and ruled it a homicide. Howerton was then arrested and charged with murder. At the trial, prosecutors argued Howerton beat Mandadi. His attorney maintained her injuries were caused during resuscitation efforts at the hospital or by a possible fall. When jurors couldn't reach a verdict, a judge declared a mistrial. A new trial was set for 2023.

Mandadi's mother, Alison Steele, and stepfather, Lawrence Baitland, believed for the second trial jurors needed more information about what happened inside Howerton's car.

"I needed to be able to show the jury what happened to Cayley," Baitland told 48 HOURS.

Steele, a scientist, and Baitland, a NASA engineer, launched their own investigation. Using autopsy photos and consulting with experts, they developed a theory.

"We believe that ... he reached from his driver's seat, hit her in the left ear and drove her head into the window and onto the lock button of the car," said Steele.

As part of their investigation, Steele and Baitland did something astonishing. They tracked down and bought Howerton's car.

"It's torturous," Baitland said of driving the car where he believes Cayley was fatally injured. "But it's also, you know, she was showing us what happened, you know. She was guiding us to this car." Next, Cayley's parents commissioned a simple video using actors to demonstrate their theory.

Would the couple's investigation change the course of the second trial?

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