Seattle, WA – Nearly a decade after a man was found dead in his Seattle apartment, authorities have charged 37-year-old Clay Fosse with second-degree murder for the killing of Thomas Hess, who police say died by mechanical asphyxia and was found with signs of blunt-force trauma and cleaning chemicals on his body.
The Incident: Body Found Bound and Scrubbed with Oven Cleaner
According to a probable cause affidavit obtained by investigators, the case dates back to February 14, 2015, when Thomas Hess was discovered dead by his roommates in his apartment located in the 2300 block of 1st Avenue in Seattle.
Police described a grisly scene: Hess’s wrists were tied behind his back with a shoelace, and his face was covered with a perforated leather mask. His body had been covered with blankets and smelled strongly of Easy-Off oven cleaner, which was also found in a can next to his feet.
Detectives later confirmed that the body appeared to have been scrubbed with the cleaner, suggesting an attempt to remove forensic evidence.
“The autopsy revealed evidence of blunt force injuries to the face, neck, and torso which included several broken bones,” the report stated.
The medical examiner ruled the cause of death as probable mechanical asphyxia, meaning Hess was killed by obstruction of his breathing pathways.
Investigation and Forensic Evidence
Building access records showed that Hess last entered his apartment around 3 p.m. on February 12, 2015, accompanied by an unknown man. Surveillance footage later showed the same man leaving the building alone about seven hours later.
Over the following months, detectives collected multiple pieces of physical evidence, including fingernail clippings, fabric fibers, and DNA samples. The samples were submitted to the Washington State Patrol Crime Lab for analysis.
More than a year later, a DNA match identified Clay Fosse as a suspect. At the time of the match, Fosse was incarcerated in Bernalillo County Jail, New Mexico, on unrelated charges.
In August 2016, detectives obtained Fosse’s DNA directly and confirmed a forensic match to evidence recovered from the crime scene.
The case saw further progress in 2024, when investigators resubmitted neck swabs and other preserved materials for DNA testing. Results in May 2024 reaffirmed the presence of both Hess’s and Fosse’s DNA, providing new confirmation linking Fosse to the crime.
Court Proceedings and Current Status
Authorities announced that Fosse has now been charged with second-degree murder in Hess’s death. He remains in custody in New Mexico, where he is currently serving a sentence for aggravated battery with a deadly weapon under the New Mexico Department of Corrections.
Records show Fosse’s criminal history includes kidnapping, false imprisonment, assault, and trespassing. Detectives noted that he had also been arrested in Washington state shortly after Hess’s murder for assault and criminal trespass, though he was not yet linked to the homicide at that time.
Prosecutors are expected to pursue extradition proceedings to bring Fosse back to Washington to face the murder charge.
The motive for the killing remains unclear, and investigators have not confirmed how Fosse and Hess knew each other or what led to the violent encounter.
Statements from Authorities and Community Impact
Law enforcement officials said the case reflects the persistence of investigators and advancements in forensic science that allow cold cases to be reopened years later.
“Even after nearly a decade, the DNA evidence told the story,” said one Seattle homicide detective involved in the investigation. “This was a brutal and deliberate killing, and the victim’s family deserves closure.”
Neighbors who lived in the apartment complex at the time recalled the incident as one of the most disturbing crimes in the area. Several said they were relieved that a suspect has finally been identified.
Background and Legal Context
“Mechanical asphyxia” refers to death caused by physical restriction of breathing — such as binding, pressure, or obstruction of the airways. Combined with blunt-force injuries and the use of cleaning agents, investigators believe the crime involved both physical assault and deliberate concealment efforts.
Forensic specialists noted that attempts to remove biological evidence using chemical cleaners such as Easy-Off oven cleaner are sometimes seen in homicide cases, though rarely with success, as modern DNA technology can detect trace evidence even years later.
Ongoing Developments and Next Steps
The King County Prosecutor’s Office has officially filed the murder charge, and Fosse will remain in custody pending his extradition hearing. Detectives continue to investigate whether anyone else may have assisted him before or after the crime.
Court filings indicate that Fosse’s first appearance in Washington State Superior Court could occur by early 2026 once transfer proceedings are complete.
Conclusion
After nine years of unanswered questions, the 2015 killing of Thomas Hess has finally led to an arrest. As prosecutors prepare for trial, the case stands as a reminder of how DNA evidence and persistence in cold-case investigations can bring justice — even after years of silence.
What are your thoughts on this case and the long-awaited breakthrough? Share your opinions in the comments below.
