Jody Loomis was sexually assaulted and murdered in 1972 while biking to a horse stable — and decades later, a trace of DNA on a borrowed boot finally exposed her killer.

Jody Loomis, left; Terrence Miller, right.Credit : Snohomish County Sheriff’s Office

Nearly five decades after a 19-year-old in Washington state was gunned down while riding her bike, a small trace of DNA finally named her killer — only for him to die by suicide hours before a jury delivered a guilty verdict.

The harrowing case is the focus of the next episode of People Magazine Investigates, “My Sister’s Boots,” airing Monday, March 2, at 9 p.m. ET on Investigation Discovery.

On Aug. 23, 1972, Jody Loomis left her family’s home in Bothell, Wash., planning to spend the sunny afternoon trail riding with her horse, Saudi. She borrowed a pair of waffle-stomper boots from her 12-year-old sister, Jana, before heading out on her white 10-speed bicycle.

Jody never made it to the barn.

Jody Loomis and her horse, Saudi.Credit: Snohomish County Sheriff’s Office

That afternoon, a young couple stumbled upon a gravely injured woman in the woods. She had been shot in the head and appeared to have been sexually assaulted. They rushed her to the hospital, but she died en route.

Deputies soon realized the unidentified victim — found without ID, her glasses askew and one boot untied — was Jody.

Investigators theorized she had been forced deep into the woods at gunpoint, raped and shot with a .22-caliber weapon as she tried to dress herself.

Suspicion swirled around several local men, including a ranch owner who had previously behaved inappropriately toward Jody a tenant who had been chopping wood nearby. But with no witnesses and no physical evidence tying anyone to the crime, the case stalled.

In 2005, cold case detective Jim Scharf reopened the file. Only a few items of evidence remained — including Jody’s boots. A state crime lab technician discovered a small trace of DNA on one boot, enough to build a profile. But at the time, there was no match in CODIS.

It would take another leap forward in forensic science to break the case open.

Terrence Miller.Snohomish County Sheriff’s Office

In 2018, investigators turned to genetic genealogy, tracing the DNA profile through family lines until they narrowed in on the Miller family, who had lived in the area at the time of the murder. One brother, Terrence “Terry” Miller, had a history of sexual violence.

Detectives surveilled Miller and retrieved a discarded coffee cup, obtaining a DNA sample that matched the profile developed from Jody’s boot.

In April 2019, 46 years after Jody’s death, Miller was charged with first-degree murder.

The trial later began in October of 2020.

On Nov. 6, 2020, after jurors had begun deliberating, Miller, 78, died by suicide from a gunshot wound. Hours later and unaware of his death, the jury returned a guilty verdict.

A judge later signed an order affirming that Miller had been found guilty beyond a reasonable doubt.

For Jody’s sister Jana, who had lent her those boots decades earlier, the verdict brought a measure of long-awaited justice.

The new episode of People Magazine Investigates is airing Monday, March 2, at 9 p.m. ET on ID.