Editor’s note: Some details in this story are disturbing.
PORTLAND, Ore. (KOIN) — A Hillsboro man who sexually abused a teenage girl he met online for several years was sentenced Tuesday to 42 years in prison, the Clackamas County District Attorney’s Office announced.
Seth Winkelhake, 41, pleaded guilty to first- and second-degree sexual abuse, first-degree sodomy, two counts of strangulation, two counts of luring a minor and two counts of using a child to engage in sexually explicit conduct.
Other charges were dismissed as part of the plea agreement. Winkelhack was working as a public affairs specialist for Washington County Clean Water Services at the time.
Officials said Winkelhak met the girl in an online chat room in late 2017 or early 2018, when he was 33 and she was 13. He claimed to be 23 years old.
Seth WayEnkelhak (Clackamas County District Attorney)
“Winkelhack convinced the girl to send him numerous nude and inappropriate sexual images and then used the photos to blackmail her, forcing her to continue sending explicit photos,” the District Attorney’s Office said. “He knew the girl’s name and several personal details. She feared Winkelhack would send the photos she shared with him to her family or others.”
In 2021, when the victim was 16, Winkelhacker pressured the victim to meet with him.
“From that point on, Winkelhacker sexually and physically abused the victim frequently at night in Oak Grove area parks. He always wore a mask and she never saw his face. Winkelhacker quickly became more aggressive and often inflicted pain on her,” officials said.
The victim described Winkelhacker as “terrible” and said he forced her to perform degrading activities and strangled her when she tried to remove his mask.
“Winkelhack pretended to be an upstanding member of the community, but underneath his appearance he exercised power and control over a vulnerable child to satisfy his own selfish desires,” said Deputy District Attorney Brian Powell, who prosecuted the case. “He will likely never see the outside of prison again.”
Authorities learned of the abuse in 2024 when a friend of the victim contacted police, who began an investigation.
“While searching Winkelhak’s home, investigators found sex paraphernalia and other items he used to abuse girls. They found incriminating photos, internet history and written communications on his cell phone,” officials said.
As part of the plea agreement, Winkelhak paid the girl $9,600 to cover counseling and therapy costs.
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