Serial Rapist Convicted of 1980s Washington Murders After Chewed Gum Provides DNA Link

In a case that finally closed two decades after the violent deaths of two women whose bodies were discovered in their Washington State apartments during the 1980s, a 68‑year‑old man identified as Mitchell A. Gaff entered a guilty plea for murder, thereby converting a long‑standing serial‑rape investigation into a homicide conviction predicated on DNA recovered from a piece of chewed gum.

The victims, both female, had been sexually assaulted before being found dead in the privacy of their residences, a circumstance that at the time prompted an extensive but ultimately unsuccessful investigative effort that failed to produce a definitive suspect, a shortcoming that would later be highlighted as a glaring deficiency in the law‑enforcement response to gender‑based violence during that era.

Only after forensic analysts, revisiting the cold case files in the early 2020s, identified a DNA profile extracted from a discarded piece of gum that matched the incarcerated rapist, did prosecutors possess the evidentiary foundation required to secure a plea agreement, an outcome that, while delivering a measure of delayed justice, also underscores the reliance on incidental biological evidence to resolve crimes that had otherwise languished in procedural oblivion for more than forty years.

The resolution of these murders, achieved through a combination of technological advancement and the serendipitous preservation of trivial evidence, nevertheless illuminates a systemic pattern wherein law‑enforcement agencies of the past failed to mobilize adequate investigative resources for sexual assault cases, thereby allowing perpetrators to evade accountability for extended periods and compelling the justice system to depend on the unpredictable preservation of seemingly inconsequential artifacts to finally close the books on crimes that ought to have been addressed with far greater vigor at the time of their occurrence.

Published: April 22, 2026