Written by Jessica J. Jurewicz-Woods.

William Earl Cosden Jr. was born on December 19, 1946 to William Earl Sr. and Janet (nee Bakke) in Baltimore, Maryland. The couple were married on June 6, 1945 and eventually settled down near Seattle in Washington and had two girls and two boys: Karen (Harris), Susan (Keller), William Jr. and Timothy. Mr. Cosden worked as a mechanic and owned a truck stop near Olympia, WA. After high school (I’m not sure if he graduated and I couldn’t find the name of the institution he attended), ‘Billy’ joined the Marines and fought in the Vietnam War. Not long after arriving back in the US, he was charged with the murder of Helen Patricia Pilkerton. The 22 year-old disappeared on April 16, 1967 and her body was eventually found by two teenage girls in a stream by Flat Iron Road in the Great Mills area of Baltimore. Two court appointed psychiatrists testified in court that the war vet ‘lacked the substantial capacity to appreciate the consequences of the crime.‘ Circuit Court Judges Perry Brown and J. Dudley Diggs determined that the then twenty-year-old Cosden was ‘insane at the time of the murder,’ which saved him from ‘hard time.’ He was sentenced to reside at  the Clifton T. Perkins Hospital in Jessup, MD until ‘he no longer constitutes a danger to others or himself under the dictates of the law.’ Regarding the verdict, Judge Diggs said that ‘the facts substantiated by the State prove that the defendant (Cosden) is really but not responsible for his actions because of mental illness.’ Just as a side note, this really passes me off. If the judges realized who exactly they had in their custody and sentenced him to prison it may have prevented the death of Katherine Devine and the brutal rape and assault of Beverly Pearson.

Four years later Cosden was released from the psychiatric hospital and moved to Washington state to be with his family. He began working at his father’s business, the Restover Truck Stop in Tumwater, which happened to be a popular hangout for hitchhikers. On November 25, 1973, Katherine Merry Devine vanished without a trace while attempting to hitchhike about 200 miles away to her cousin’s house in Rockaway, Oregon. The next day, a coworker noticed bloodstains in Cosden’s truck, which coincidentally caught fire immediately after. Although LE had their suspicions about Cosden being involved in the 14 year old’s death, they had no proof tying him to the crime.

William managed to fly under the radar until 1975, when he was arrested for the brutal assault and rape of Beverly Pearson (in some older newspaper articles she has the last name Frederick). Early in the morning on November 30, 1975, thirty year-old Cosden brutally raped and assaulted the 24-year-old, who was a customer at his truck stop. The weather that night was snowy and driving conditions were treacherous, and he asked the pretty young pharmacy technician if she’d like him to follow her home to make sure she got there safely. She politely declined his offer however he insisted. At some point during their drive, Billy purposely drove his truck into a ditch then pretended to need help getting it out. After Beverly got out of her car to check on him, Cosden subdued her by hitting her on the head from behind and threatening her with a rubber mallet. Pearson told him that she would ‘do anything if he wouldn’t hurt her’ and at one point during the assault Billy grabbed her by the throat and asked how she was going to explain her ‘new bruises.’ After raping her twice, he took her to his property in Maytown. During the drive, Beverly tried to jerk the wheel in an attempt to make him lose control, and even tried to escape by trying to open the door and crawling out. She was unsuccessful.

The attack took place in a secluded wooded area near Maytown Road. Miraculously, Beverly was able to convince her attacker to let her go and he was arrested a few days later, just hours after she made the report to police. Pearson told the sheriff’s department that she was assaulted by a man ‘named Bill at the Lathrop Road Truck Stop.’ FBI Agent Myron Scholberg said the victim’s hair was found on Cosdens overalls and in his truck, which helped officially link him to the crime. A second federal agent named Allison Semmes positively identified stains that were left behind on Beverly’s underwear and panty hose as Cosdens sperm; the same substance was found on the overalls he was wearing that night. Strangely enough, when law enforcement examined his truck they were unable to find any identifiable fingerprints.

At Cosdens’ trial, a nurse that treated Pearson the night she was assaulted testified that she had ‘bruises and reddened areas around her head and shoulders’ and a Doctor said her injuries were consistent with the results of wounds caused by a blunt object. Dr. Torre Nielson (a Psychiatrist for the defense) said that ‘the performance of two sexual acts in succession in cold weather was highly unlikely.’ He also said that it’s common for a man to experience impotence when thinking of his wife and child. A Seattle based pathologist told the jury that based on lab tests done at around 9 AM later the same day the attack took place, no intercourse had occurred in the previous 12 hours.

While testifying in his own defense, Cosden said when Beverly first saw him early that morning she waved to him, flirting as if they knew each other and happily accepted his offer to follow her home because of the weather. The defendant said that Pearson deserted her pickup in the middle of the intersection at 101st Ave and Case Road, backing it up into the wrong lane then leaving it to get in his vehicle ‘to talk.’ He went on to say that she sat in the middle of his seat, wrapped her arms around him, and asked him to drive them to a place where they could ‘be alone.’ William testified that she talked about her divorce and that he never threatened her or hit her in any capacity. He took her to some property he owned in Mayfield and at no point during their time together did Pearson try to get away from him or leave his company; he also said that at any point if she changed her mind about being with him he would have stopped everything and taken her back to her pickup. He shared with the jury that he never threatened her with a gun ‘hidden under the seat, as she had testified’ and didn’t even keep a weapon in his truck. The married man also claimed that he completely turned down her advances, and that he couldn’t partake in sex with Beverly because all he could think about was his wife and child. When asked how he felt about what happened, Cosden said that he ‘felt like a damned fool.’

Cosden also testified that Beverly drove to his house on January 5, 1976 looking for him. After she pulled away, he immediately called his Attorney Don Taylor and told him about the incident.

On February 18, 1976 William Earl Cosden Jr. was sentenced to 32 years in prison for the rape and brutal assault of Beverly Pearson. He was up for parole in 1990 however the board denied his release, saying he was not safe to be released into the community. Apparently Cosden had quite a temper and on two separate occasions he was brought back to prison after being thrown out of pre-release housing units. In 1999 he was up for parole again but was denied.

In 1986, Thurston County Detective Mark Curtis got a court order for Cosdens blood, but because the technology wasn’t available at the time the sample sat in evidence for so long that he forgot it was even taken. Because of some grant money available through the WA state Attorney General’s HITS program, Curtis was able to take part of the DNA sample to compare to Devines. In 2001, a comparison was done and the test came back a match: William Cosden Jr. killed Katherine Merry Devine. After the successful identification, Detectives Joe Vukich and Brian Schoening went to the prison Cosden was being housed at on McNeil Island and questioned him about his involvement with the murder of Devine. He claimed to know nothing about it.

In 2002 the rest of the DNA sample Cosden provided in 1986 was used in a second analysis, and there was no doubt about it: he was the man that killed Kathy Devine. Detectives David Haller and Tim Rudolf went to talk to Cosden about the positive identification; this time he said he may have had sex with her but didn’t kill her. He was furious when detectives arrested him for the 1973 murder, despite already being in prison. Thankfully, prosecutors were able to argue that Kathy’s DNA was a match to the blood found in his truck and on his clothes. William Cosden Jr. was 55 when he was sentenced to life in prison without the chance of parole in June 2002. Former Deputy Prosecutor Philip Harju said that he was ‘an obvious danger to society,’ and former Thurston County Superior Court Judge Daniel Berschauer agreed with his assessment before passing on the life sentence.

William Earl Cosden Jr. died at the age of 69 in 2015 while incarcerated outside of Seattle, Washington. William Cosden Sr. passed away on December 8, 1983, and Mrs. Cosden died on May 3, 2014 at the age of 88. Susan Cosden-Keller began her career as a teacher but went back to school for her nursing degree. Karen Cosden-Harris worked as a reading specialist at Evergreen Elementary School in Washington. Timothy Cosden was a massage therapist until recently, when on October 5, 2022 his license was suspended after he was accused of sexual assault (Bilbao, The Olympian).*

On Easter Sunday 2023, an episode of the Discovery Plus show ‘Evil Lies Here’ premiered that featured William Cosden Jr.’s two younger sisters. Karen and Susan also fell prey to their older brother, who made them keep his secrets to themselves. The two women lost touch over the years, each one becoming busy with their own careers and lives all while trying to heal and move on from their painful childhoods. But after Karen received a terminal diagnosis of stage four lung cancer, they reunited on the show to talk through their shared trauma in hopes of healing and coming to terms with what happened to them in their younger years. Karen Cosden-Harris sadly passed away on November 4, 2022.

* Bilbao, Martin. ‘Thurston County Massage therapist, 68, suspended for alleged sexual assault.’ October 12, 2022. https://www.theolympian.com/news/local/article267212417.html