Mitchell Gaff pleaded guilty to two decades-old murders in Snohomish County court after DNA evidence collected from chewing gum connected him to the cold cases.

Detectives obtained Gaff's DNA through what investigators described as a strategic operation involving discarded chewing gum. The genetic evidence linked him to murders that had remained unsolved for approximately two decades.

The case represents one of multiple recent cold case developments in the region. In a separate matter, Robert McCaffrey has pleaded not guilty to charges in the 1990 death of Lisa Marie McBride. Investigators allege McCaffrey confessed to the decades-old murder, though he maintains his innocence in court proceedings.

McCaffrey's case has drawn additional attention as his wife disappeared years ago under circumstances that remain unresolved. Authorities have not publicly connected the two cases but continue investigating his background.

The use of DNA evidence to solve cold cases has become increasingly common as technology advances and databases expand. Both cases highlight law enforcement's continued efforts to pursue justice in long-dormant investigations, even when decades have passed since the original crimes occurred.