DNA databases are helping solve Pierce County cold cases
Jun 28, 2018, 5:51 AM
Pierce County Prosecutor Mark Lindquist. (File, Associated Press)
(File, Associated Press)
DNA databases like Ancestry.com are helping to solve cold cases decades after the crimes occurred.
Pierce County Prosecutor Mark Lindquist explained to KIRO Radio’s Dori Monson that private DNA banks led Washington detectives to Illinois resident Robert Washburn, who was arrested for the 1986 murder of 13-year-old Jennifer Bastian in Tacoma.
Back in 1986, the DNA allegedly left by Washburn at the scene of the crime was too limited to help in finding a suspect. However, Lindquist said advancements in DNA technology allow detectives to find a match from smaller samples.
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Helping detectives is the prevalence of online DNA records, such as websites like Ancestry.com. These websites collect DNA samples. People on the system can connect with long-lost relatives.
“Back in 2013, the DNA technology advanced to the point where we could pull a profile from a very small sample that was left at the crime scene in 1986,” Lindquist explained.
However, Washburn was not in the criminal database because he had never received a conviction.
After looking through private databases, including those found on Ancestry.com, detectives were able to find an entire family’s DNA that had similarities with the crime scene DNA. That eventually led them to Washburn.
“We can now develop a profile match from an infinitesimal sample,” he said.
Lindquist added with a laugh, “We’re now at a point where it is almost like movies and TV — from these infinitesimal samples, we can pull a useful profile.”
There is still progress to be made, however. The national solve rate for homicides is just 63 percent. In Pierce County, this number is closer to 80 percent. Lindquist said that Pierce County’s solve rate is on the rise because of DNA advances and also because gang violence is dropping.
According to Lindquist, the most difficult homicides to solve are gang homicides, due to uncooperative witnesses, and stranger homicides such as the Bastian case, where there is no connection between the perpetrator and victim.
Washburn has been arraigned and is being held on $5 million bail. Lindquist expects the case to take at least a year to go to trial.
