An anonymous reader shares a report from The New York Times: The Golden State Killer raped and murdered victims all across the state of California in an era before Google searches and social media, a time when the police relied on shoe leather, not cellphone records or big data. But it was technology that got him. The suspect, Joseph James DeAngelo, 72, was arrested by the police on Tuesday. Investigators accuse him of committing more than 50 rapes and 12 murders. Investigators used DNA from crime scenes and plugged that genetic profile into a commercial online genealogy database. They found distant relatives of Mr. DeAngelo's and traced their DNA to him.
"We found a person that was the right age and lived in this area -- and that was Mr. DeAngelo," said Steve Grippi, the assistant chief in the Sacramento district attorney's office. Investigators then obtained what Anne Marie Schubert, the Sacramento district attorney, called "abandoned" DNA samples from Mr. DeAngelo. "You leave your DNA in a place that is a public domain," she said. The test result confirmed the match to more than 10 murders in California. Ms. Schubert's office then obtained a second sample and came back with the same positive result, matching the full DNA profile. Representatives at 23andMe and other gene testing services denied on Thursday that they had been involved in identifying the killer.
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