Cold Case Project: 20 years later, family still seeks answers in Pinnacle Lake double homicide

Nearly two decades after a mother and daughter were shot and killed on a remote hiking trail in the Mount Baker-Snoqualmie National Forest, their family is still searching for answers and hoping that someone’s memory might finally unlock the mystery.

On July 11, 2006, Mary Cooper, a Seattle mother, and her adult daughter Susanna Stodden set out for what was supposed to be a routine hike. The pair were experienced hikers who went out often; this trip began like many others, but this time, they didn’t come home.

A day that started like any other

Mary’s husband and Susanna’s father, David Stodden, still remembers the details of that morning.

“It was kind of a day like any other. Mary and Susanna had gone on quite a few hikes, and I just said goodbye to Mary at 8 a.m.,” Stodden recalled.

Mary drove to pick up Susanna, and together they headed out the Mountain Loop Highway. Their original plan was to hike Mount Pilchuck, but heavy snow that year forced a change. Somewhere along the way, they decided to hike the Pinnacle Lake Trail instead.

While Mary and Susanna were on the trail, David spent the day working on a house he and Mary were renovating. Later, he went on a training ride for the Seattle-to-Portland bike event.

“Even though on the bike ride I tried to call Susanna and Mary’s phones a few times and didn’t get through. When I got done with the bike ride, they still were not answering the phone,” David said.

At first, he assumed they had changed plans, stayed out later, or gone to dinner. But as darkness fell and there was still no word, his concern grew. He began calling authorities.

A late-night knock delivered devastating news

David said he made several calls to the Washington State Patrol and then to the Snohomish County Sheriff’s Office, fearing at first that Mary and Susanna might have been in a car accident.

“I could tell right away that they knew what had happened, or they knew something had happened. But they weren’t going to tell me,” David said.

Worried they might have slipped on snow near their planned route, David grabbed an ice axe and prepared to drive up to search. But before he could leave, detectives called and asked him to wait at home.

“They came over and told me that Mary and Susanna had been killed, and they didn’t know if a wild animal had killed them, which I knew was not true,” he recalled.

That night, detectives interviewed him about his day, then later returned to take his computer and other items. By then, it was the early hours of the morning.

Treated as a suspect

Like in many homicide investigations, David quickly found himself under intense scrutiny as an early suspect.

“It was pretty humiliating, and it didn’t make a lot of sense,” he said.

Despite his grief, he cooperated fully, including taking a polygraph test.

“I took the polygraph twice, and then actually I took it again 12 years later, and basically I answered the questions the same every time,” David said. “I know the third time they said I passed it. I answered the questions the same all three times.”

Yet even after that, David said some basic matters remain unresolved. He noted that authorities still have not returned Mary’s wedding ring and have been unwilling to complete paperwork he needs to access her retirement account.

“I’m not sure. I think it’s probably a control thing with them. They need to somehow control all the parts of the investigation, and I’m part of it,” David said.

A single, lingering clue: a red car

Despite years of work, no suspect has ever been publicly identified in the murders of Mary Cooper and Susanna Stodden.

When asked what information might help finally break the case open, David points to one detail he only learned from detectives years after the crime.

“One of them mentioned that there was a report of a speeding red car coming down the Pinnacle Lake Trail Road that day, which I had never heard before,” David said.

He believed that clue, a red car speeding down the Pinnacle Lake Trail Road on the day of the murders, is significant and should have been shared more broadly with the public.

“That is actually the only clue I’ve ever heard that makes any sense from the detectives,” David said. “I think that when they have information like that, they should put that out there.”

A plea for transparency, public help

David believed investigators need to engage the public more fully if this case is ever going to be solved.

“I think the detectives could do a lot more to reach out to the public to try to solve this case,” he said.

On the day Mary and Susanna were killed, there was only one way out from the Pinnacle Lake area back to the Mountain Loop Highway, and then 15 miles back to Granite Falls. With people fishing along the river and others on the road, David thought that a speeding red car would have been noticed.

“Realistically, a lot of people would have seen that car drive by; people in Granite Falls would have seen it also. If there was anything odd about it, speeding would be the thing I’d be looking for,” David said.

How you can help:

As this latest Cold Case Project segment airs, Mary Cooper and Susanna Stodden’s family are once again appealing to the public for help.

If you remember a red car speeding down the Pinnacle Lake Trail Road on July 11, 2006, or if you saw anything that seemed unusual or suspicious on the trail, the road, or along the Mountain Loop Highway that day, you are urged to come forward.

The hope is that this report generates some new leads. Anyone who saw that red car, or anything else that they may have thought was suspicious all of those years ago, call Crime Stoppers at 802-22-TIPS and give that information. There is still a reward available for information that leads to an arrest and charges.

After nearly twenty years, one memory, one tip, or one long-held piece of information could finally bring justice for Mary Cooper and Susanna Stodden, and some measure of peace to the family that has been waiting ever since.

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