SPOKANE, Wash – It may have taken almost 40 years to the day, but the search for a man suspected of killing a woman in east Spokane in 1986 led police to the home where the suspect has been living all along.
Police arrested 74-year-old David Tibbett at his home on East Decatur. It’s the same home Tibbett lived in when police say he killed Mary Ann Turner in 1986.
The details of the case lay out like a true crime television show and reflect what a dangerous time it was in Spokane for women working on the streets.
Court records also show Turner’s fight with her killer would help bring the promise of justice almost 40 years later.
The Murder of Mary Ann Turner
The night of November 4, 1986, police found a woman dead in an alley on South Ivory, just south of East Sprague near the freeway.
Police identified her as 32-year-old Mary Ann Turner.
She was partially clothed and wearing a scarf that may have been used to strangle her. One of her earrings was found in the dirt nearby.
“Crime scene and autopsy photographs indicate Turner fought her killer violently,” investigators wrote in a search warrant. “Photographs of her fingernails were especially indicative of her efforts to fight.”
Her hands were “heavily soiled” and her fingernails were “clogged with dirt”. Inside those fingernails, though, was a clue that would later help solve the case.
An autopsy revealed Turner was strangled to death. Investigators collected swabs from her body and preserved her fingernail samples for evidence.
Witness becomes a murder victim
As part of the investigation into Turner’s murder, police interviewed Yolanda Sapp. Sapp and Turner were both prostitutes and Sapp told police she and Turner had been working the streets together for about a month.
Sapp described watching Turner get picked up by a burnt orange two-door car early on the morning of November 4th.
She never saw Turner again.
About a week later, police gave Sapp a book of pictures to look through. A search warrant says Sapp picked out a 1977 Ford Thunderbird that looked the vehicle that picked up Turner.
She described the driver as a white man in his 40s with a “mushroom” haircut and glasses.
Four years after sharing this potentially crucial evidence with police, Yolanda Sapp was found dead in a murder that would also go unsolved for decades.
In 2014, police charged Donna Perry with the murder of Sapp and two other women. At the time of those crimes, he was a man named Douglas.
WATCH: 509’S MOST NOTORIOUS CRIMES – DOUGLAS OR DONNA – THE RIVERBANK MURDERS
DECADE OF VIOLENCE
In a news release sent about Turner’s murder, Spokane Police ask for any information, specifically related to prostitutes. The release references this being one of three women murdered in east Spokane within two years.
Another was Ruby Doss, who was found dead in January of 1986. Her murder also sent unsolved for many years, ending with the arrest and conviction of a man named Richard Aguirre, who at the time of his arrest in 2015, was working as a police officer in Pasco.
Several years later, more women were picked up off the streets of Spokane and murdered by a man named Robert Yates. Yates was convicted of killing 16 people.
That 1986 news release from police also mentions the murder of a 12-year-old which was also unsolved. Marsi Belecz was found dead in 1985 just two days after running away from home.
Her murder went unsolved until 2020 when a private DNA lab linked evidence to her killer.
The Case Goes Cold
After Turner’s murder and that plea from police, tips starting coming in about the murder and a possible suspect.
One person called a tipline called Secret Witness and named David Tibbett as a possible suspect.
The tipster said Tibbett had a copper brown Ford Elite and that he was “known to hang around the hookers.”
When detectives found Tibbett, he was already in jail for attempting to elude police, a charge that came after Turner’s murder.
He refused to speak with police, but investigators determined he had a 1975 Ford Elite registered to his home at 1817 E. Decatur.
That’s where the case apparently went cold.
Examining the Evidence
Investigators had a trove of possible evidence collected from the crime scene, including four cigarette butts, the fingernail clippings and the swabs.
In 1987, investigators sent the items to the Washington State Crime Lab. They found microscopic amounts of blood in the fingernails. Technology at the time didn’t allow such a small amount to be tested and the evidence was sent back to Spokane County.
In 2008, an SPD detective submitted the evidence to another private DNA lab. The lab found semen from several of the swabs of Turner’s body, a partial DNA profile from one of the cigarette butts and a DNA profile from the fingernail clippings. That DNA was a mix of Turner’s and an unknown male.
Police uploaded that DNA profile into a national database.
Search warrants filed in the case show that as technology got better, smaller amounts of DNA could be tested. But, even as recently as 2025, they had no match.
Forensic Genetic Genealogy
By 2025, technology had caught up with the case.
In September, police sent the DNA to Othram Lab, a lab in Texas that specializes in these cases.
By December of 2025, Othram said it had had started the forensic genetic genealogy process, where investigators access public genealogy databases.
It’s the technology Othram used to help investigators match evidence to Bryan Kohberger, who killed four students at the University of Idaho in 2022.
In January 2026, Othram told police the profile was linked to three brothers: Darrel Tibbet, Daniel Tibbett and David Tibbett. Darrel and Daniel both died in 2013.
David Tibbett was still in Spokane – and, still living in the house on E. Decatur
Police found that David Tibbett was arrested in Spokane in 1968 for sexual assault and again for attempted rape in 1971.
During an evaluation at Western State Hospital, David Tibbett was designated a sexual psychopath.
“The Ruse”
In November 2025, just a few months before the Othram lab made the link to David Tibbett, Tibbett reported his car was stolen.
The vehicle was ultimately found by U.S. Border Patrol and returned to Tibbett.
In February, police decided to “employ a ruse” and sent a letter to Tibbett about that stolen car.
The letter asked him to confirm his vehicle was no longer stolen by signing the letter and mailing it back to Spokane Police.
According to the search warrant, Tibbett signed the letter, licked the envelope and sent it back.
Police took the envelope to the Washington State Crime Lab, asking forensic investigators to compare it to DNA found under Mary Ann Turner’s fingernails.
March 11th, police got the news: it was a match.
On October 21st, police asked a judge to sign a search warrant granting them permission to search Tibbett’s home.
They placed him under arrest for second degree murder.
Almost exactly 40 years after Mary Ann Turner’s body was found in that Spokane alley, the man accused of killing her will face charges for the crime.
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