Arlington man charged in death of sister

EVERETT — An Arlington man was charged Friday with his sister’s murder, and police continue to investigate the circumstances surrounding the death of his elderly mother hours earlier.

David Thorsen, 50, has been in the Snohomish County Jail since June 10. He was arrested after a Snohomish County sheriff’s sergeant discovered the body of Karen Harris, 53, under a blanket in a field near her parents’ Arlington home.

Harris died of homicidal violence, specifically blunt-force injuries. Police believe Thorsen killed his older sister and then hauled her body out to the field with a riding lawn mower. Detectives found blood in the house and on the mower. They also discovered a pile of blood-spattered clothes. The plaid shirt and shorts appeared to be the same clothes that Thorsen was seen wearing June 8 in business surveillance footage, court papers said.

David Thorsen first called police about 5:45 a.m. June 8 when he reported finding his mother, 80, dead at the bottom of a staircase leading to the basement. While investigators were there Harris showed up. Deputies left the property just before 10 a.m., wrapping up their investigation.

Betty E. Thorsen’s death initially was not believed to be suspicious, but now is being reviewed by the county medical examiner. Findings are pending. Her injuries appear consistent with a fall, Snohomish County deputy prosecutor Katie Wetmore wrote in charging papers.

Because of the suspicious circumstance surrounding the women’s deaths, homicide detectives also looked into the April 11 death of the suspect’s father. The King County medical examiner, however, called Jack Thorsen’s death an accident from “a presumed fall.” He was 84.

David Thorsen had been living with his mother. Police reportedly found a couple of letters in his room dated May 27 and addressed to his mother. One contained disparaging language and curse words directed at Betty Thorsen. In the letter, the suspect wrote that he hoped his mother perished, court papers said. The second letter appeared to be a suicide note in which David Thorsen spelled out who should get his property with directions that Harris not receive anything. That letter also contained disparaging remarks about his sister, Wetmore wrote.

His sister’s death came to the attention of police after her son reported her missing. He was worried when he hadn’t heard from his mother by the end of the night on June 8. He went to his grandparents’ house around 11 p.m. and found his uncle extremely drunk. He returned a couple of hours later and found his mother’s car parked on the property behind an outbuilding.

He also told police that he saw his uncle a few hours later riding on the lawn mower with a long tow strap attached.

Police came to the property to investigate the missing person report. Thorsen apparently was attempting to end his own life by breathing exhaust fumes from his car when a Snohomish County sheriff’s deputy approached him, court papers said.

Detectives later interviewed neighbors, who reported hearing a loud argument the day before Harris’ body was discovered. Witnesses reported hearing a woman yell “Don’t! Don’t!” Other neighbors reported hearing a screaming match between a man and a woman.

Investigators learned that several hours later Thorsen used his deceased mother’s bank card to withdraw $500 and purchase about $114 worth of groceries and alcohol from the Arlington Safeway.

Thorsen is being held on $1 million bail. He is expected to answer to the second-degree murder charge early next week.

Diana Hefley: 425-339-3463; hefley@heraldnet.com.

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