FAIRFIELD (CBS SF) – Cold case detectives with the Fairfield Police Department have announced that they recently identified the suspect in a 1983 brutal sexual assault and beating murder of a woman in her Fairfield home, but that the suspect committed suicide shortly after they contacted him.

Police had fingerprint evidence identifying 48-year-old Robert Hathaway as Priscilla Strole’s suspected killer, and they had a warrant to obtain a DNA sample from Hathaway, investigators said.

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Hathaway was at home when detectives Dave Hoen and Mel Ferro went to his residence on Fourth Street in Fairfield on Feb. 11. They got Hathaway’s DNA sample, but Hathaway denied any involvement in the murder, according to police.

Four days later, Hathaway hanged himself at his residence. In a suicide note to his wife, Hathaway stated he “took the coward way out,” police said.

The murder case was officially closed on Feb. 20 when Hathaway’s DNA sample matched semen collected at Strole’s home where she was sexually assaulted and killed, investigators said.

Priscilla Strole (Fairfield Police Dept.)

Priscilla Strole (Fairfield Police Dept.)

“With the suicide of Robert Hathaway, the family of Mrs. Strole will never know why Hathaway killed Mrs. Strole,” Fairfield police Sgt. Troy Oviatt said in a press release Tuesday.

What police and Strole’s family do know is that Hathaway was a friend of Strole’s son Kyle Stracner, Oviatt said.

Stracner, then 15, had left his home at 930 Buchanan St. around 7:30 p.m. on Aug. 31, 1983. He planned to spend time with friends, and his mother Priscilla expected him home by 10 p.m., police said.

When Stracner returned home around 9:45 p.m. and knocked on the door, no one answered, police said. Stracner looked into a window and saw his mother lying on the floor. When he entered the house through an unlocked window, he saw that his mother had been beaten do death, Oviatt said.

Stracner went to a neighbor’s house and called police, who found Strole’s naked body on the living room floor.

“It was a very gruesome homicide scene. There was a violent struggle,” Oviatt said.

Strole had been sexually assaulted, and she had suffered injuries to her face and head from kitchen knives, a can opener and a piece of decorative wood, police said.

“All the items used were from the home, Oviatt said.

The house had been ransacked and many items were broken. The killer took a jewelry box went through drawers and closets, he said. Police believed the assailant was likely let into the house because there were no signs of a forced entry, Oviatt said. Hathaway, who was 17 in 1983, knew Kyle Stracner and his mother.

“She would have known him as her son’s friend. He would not be a stranger,” Oviatt said.

Hathaway and Stracner went to the same school, and Hathaway had been to Strole’s house previously, Oviatt said.

Police collected fingerprints and semen from the crime scene, but no matches were found when the fingerprints were run through what is now the Automated Fingerprint Identification System, or AFIS, on Sept. 27, 1983, Oviatt said.

Investigative leads were followed but no suspect was identified, Oviatt said. Ferro and Hoen revived the investigation of the cold case murder in early 2012.

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“The case was never closed. Homicides remain open. We don’t put the case in a box on a shelf, we revisit them periodically,” Oviatt said.

Because of scientific advancements in DNA analysis, Ferro and Hoen sent the semen collected at the murder scene to the California Department of Justice’s Sacramento forensics laboratory in April 2012.

The lab developed a DNA profile from the semen and uploaded it into the Combined DNA Index System, a nationwide database of DNA evidence collected from criminals and during violent crime investigations.

There was no match in the system to the DNA collected at the scene, Oviatt said.

Undaunted, Ferro and Hoen realized that the suspect’s fingerprints that were run through AFIS in 1983 were compared only to fingerprints on file at that time, and that thousands of additional fingerprints were uploaded into the system between 1983 and 2014, Oviatt said.

Ferro and Hoen thought that if the prints were run through the system again, they might get a match.

On. Jan. 20 of this year, Ferro and Hoen retrieved the fingerprints taken from the 1983 crime scene and gave them to the Solano County Latent Prints Bureau.

On Jan. 28, they learned that prints from the crime scene matched the fingerprints on file for Hathaway, who had been arrested in December 1986 for burglary.

Ferro and Hoen then got a warrant from Solano County Superior Court Judge Donna Stashyn to get a DNA sample from Hathaway.

Oviatt said police would have arrested Hathaway for Strole’s murder once they had a DNA match linking him to the crime scene.

No one else is believed to have been involved in the killing.

“There were no other prints or DNA evidence at the crime scene. He committed the crime and acted alone,” Oviatt said.

Kyle Stracner died several years ago, and Strole’s brother still lives in Fairfield, according to Oviatt, who said the brother was surprised that the case had been solved.

“He was relieved. He’s been living with the crime for 31 years, and he’s very appreciative of the police,” Oviatt said.

Some of Strole’s relatives still live in the Bay Area, Oviatt said.

“There are still questions that will never be answered, but at least the family has some closure,” Oviatt said.

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