By Nina Giraldo, CNN
(CNN) — Susan Logothetti and two colleagues stood outside the yellow home in Everett, Washington, donning T-shirts and holding flyers promoting a chewing gum company.
Mitchell Gaff opened the door wearing pajama pants, welcomed the trio into his house and agreed to a taste test, sampling different sticks of gum with enthusiasm, Logothetti recalled of the January 2024 encounter.
When the time came for Gaff to try a new flavor, one colleague held out a small dish, Logothetti said.
“I remember watching him spit the first piece of gum into the ramekin and seeing the saliva, and it was very hard for me to contain my excitement,” Logothetti told CNN.
Gaff had unknowingly given three undercover detectives the DNA they needed to confirm his connection to a 1984 rape and murder, according to an affidavit of probable cause filed in March. The “gum ruse” is cited in the affidavit.
Gaff, 68, a convicted rapist, admitted April 16 to the killing of Judy Weaver and also of Susan Vesey four years earlier, according to court documents. He faces up to life in prison at his scheduled sentencing on Wednesday.
The investigations into the murders of the two Washington state women in 1980 and 1984 – back then regarded as unrelated – led to persons of interest in each case but no prosecutions.
Four decades after Weaver’s murder, forensic scientists found the DNA extracted from the gum was consistent with evidence found on her body, court documents stated. The discovery, and the eventual connection between the two murders, marked a breakthrough in the investigations and showed how crucial modern DNA technology is in solving cold cases.
Beyond that, the identification of the killer also has allowed families who lived for so long under the dark cloud of suspicion to heal and brought some relief to a woman Gaff attacked before the murders.
For closure to ultimately happen, the Weaver and Vesey cases “just needed science to catch up,” Logothetti said.
DNA profiling helped catch killer
Vesey was 21 and a married mother of two children, both less than 2 years old, when she was murdered in July 1980.
Gaff was “trying random doors and found the victim’s door unlocked” and proceeded to tie up, beat, rape and strangle Vesey, he admitted in his guilty plea statement. Four years later, Gaff attacked Weaver, a 42-year-old mother, in her bedroom, which he then set fire to in an apparent attempt to destroy evidence, according to the statement.
“Before leaving I wrapped cords around her neck and lit the corner of the bedspread in an attempt to cover up my crime and with the intention of killing her,” Gaff said. “Ms. Weaver died because of my actions.”
Gaff said in his statement he did not know either woman prior to each attack. Heather Wolfenbarger, Gaff’s defense attorney, declined to comment.
At the time of the murders, DNA profiling had yet to become a useful forensic tool. In Weaver’s case, however, law enforcement “had the foresight” to call the lab about obtaining vaginal swabs, which led them to submit the evidence a few hours after her death, according to court documents.
The case file on Weaver’s murder that Logothetti ultimately inherited from her predecessors at the Everett Police Department brimmed with outlandish theories around her death involving money laundering and cocaine. Weaver’s boyfriend at the time of her murder died in 1994 as the main suspect in her case, Logothetti said.
The emergence of DNA profiling ultimately led law enforcement to revisit Weaver’s murder in 2020, court documents said.
Lisa Collins, a forensic scientist at Washington State Patrol,