Sheriff sees link between Yates, local unsolved double murder

By SCOTT NORTH and CATHY LOGG

Herald Writers

Snohomish County detectives are investigating whether a serial killer from Spokane may be connected to the deaths of a young British Columbia couple whose bodies were found near Monroe and Burlington in late 1987.

Sheriff Rick Bart this week said at least one unsolved murder here has enough similarities to Robert Yates’ crimes that he has directed additional investigation.

The body of Jay Roland Cook, 20, was discovered Nov. 26, 1987 — Thanksgiving Day — by hunters who were near High Bridge about two miles south of Monroe. He had been strangled.

Cook’s girlfriend, Tanya Van Cuylenborg, 18, had been found two days earlier, shot to death and dumped in a wooded area near Burlington in Skagit County. She was partially clothed and had been sexually assaulted.

The couple had been on a trip to Seattle when they were killed.

Bart, a former homicide detective, investigated the Cook-Van Cuylenborg killings. He said he had a sick feeling of familiarity when he learned that Yates had admitted shooting a young couple in 1975 near Walla Walla and dumping their bodies outdoors. The victims, in their early 20s, were having a Sunday afternoon picnic.

Yates, who grew up in Oak Harbor, has admitted dumping one of his victims’ bodies in Skagit County, just months after the Cook-Van Cuylenborg murders. Stacy Elizabeth Hawn, 23, disappeared from Seattle in July 1988. Her skeletal remains were found south of Big Lake in Skagit County on Dec. 28, 1988. Yates has told investigators that he murdered Hawn while on military leave.

Snohomish County officials met with detectives involved with the Yates case two weeks ago and learned he was in Washington at the time Cook and Van Cuylenborg were killed, sheriff’s detective Gregg Rinta said Thursday.

Rinta said there are enough similarities between the young couple’s 1987 killings and Yates’ other crimes that he’s asked state experts to compare genetic evidence from the crime with Yates’ DNA.

"I am actively looking at him in this double murder, comparing physical evidence that we have," Rinta said.

But Skagit County’s prosecutor apparently has ruled out a link.

"There’s no reason to believe he’s connected to any other homicides in Skagit County," including the Cook-Van Cuylenborg deaths, Skagit prosecutor Thomas Verge said Thursday. The double murder didn’t fit Yates’ pattern, Verge said.

Despite Yates’ admissions to some murders, Spokane County sheriff’s investigators haven’t closed their investigation. They’re concerned about the large gaps between his known killing sprees.

Yates has admitted to 13 killings committed in 1975, 1988 and 1996-98.

"Studies indicate that (serial killers) just don’t stop. I think there’s reason to continue looking," sheriff’s spokesman Cpl. Dave Reagan said Thursday.

"We’ve had 12 unsolved deaths of women back to 1984 in Spokane that we’re going to be taking a look at," he said.

Author Tomas Guillen urges them to keep looking.

"It’s likely he has done other things and is not ‘fessing up to them," said Guillen, a Seattle University professor. He wrote "The Search for the Green River Killer," about the Seattle-area serial-murder case.

While all the murders Yates is confessing to involved shootings, Guillen said serial killers generally like to work very close to their victims.

"Police would be making a big mistake if they only looked at homicides involving handguns,’" Guillen said.

They should also be looking at those involving other means, such as strangulation or bludgeoning, he said.

Snohomish County has a number of unsolved murders in which victims were strangled or bludgeoned before their bodies were dumped in wooded areas.

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