Court records obtained by The Associated Press show that in March 2017 investigators in Clackamas County, Oregon, convinced a judge to order the 73-year-old man to provide a DNA sample.
VIDEO: CoCo County Investigator Paul Holes is '100 percent sure' they have 'Golden State Killer'
ABC7 News spoke with newly retired cold case investigator, Paul Holes, about his search for the "Golden State Killer." The obsession, the haunting crimes, and his quest to help ease victims suffering is a story you'll want to hear from him.
The documents said they used a genetic profile based off DNA from crime scenes linked to the serial killer and compared it to information from genealogical websites. They created a family tree and used public records to identify the Oregon man.
Investigators also cited a rare genetic marker, which the Oregon man shared with the killer, to get the judge to issue the order.
VIDEO: Forensic psychologist examines mind of accused 'Golden State Killer'
A well known criminal pyschologist from the Valley offers insight into the crimes deangelo is accused of committing.
Earlier this week, police say they arrested the right man for a dozen killings and 50 rapes from 1976 to 1986. He is Joseph DeAngelo, a 72-year-old former police officer who lived in the Sacramento area.
FROM THE ARCHIVE: 'Golden State Killer' investigation moves to Walnut Creek in 1978
FROM THE ARCHIVE: 'Golden State Killer' investigation moves to Walnut Creek in 1979
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