The Golden State Killer terrorized Northern California between 1976 and 1986, when he committed 50 known rapes and 12 known murders, as well as burglaries and other horrendous crimes.
Sacramento and surrounding areas found themselves living in a state of total blind fear as a seemingly faceless suspect could simply not be apprehended by the police. Suspect after suspect was cleared. But in April 2016, police announced they were mounting a full scale invesitgation on the case.
And on April 24th, 2018, conclusive evidence led to former police officer Joseph James DeAngelo. He was arrested. How, you ask? DNA and Ancestry Websites.
According to police, they obtained a matching sample of DeAngelo's DNA from something he discarded. But they worked backwards to get there.
As per the San Francisco Chronicle:
"Law enforcement officials said Thursday that they used a genealogical site [GEDMatch] to to link the suspect’s DNA to a pool of suspects, which eventually helped them narrow the search to 72-year-old Joseph James DeAngelo, the ex-cop suspected of 12 murders and at least 48 rapes."
Apparently, a relative of DeAngelo's had done a DNA test and the match was near enough to DNA found at the crime scene that they were able to build a pool of suspects.
Confirming reports, two sources tell me police tracked down the alleged East Area Rapist/Golden State Killer by running crime-scene DNA against consumer genealogical websites, giving them possible relatives of the target, then building a pool and narrowing from there.— Demian Bulwa (@demianbulwa) April 26, 2018
23andMe to me, re: Golden State Killer: "The answer is no, we have not received inquiries regarding this case. Broadly speaking it's our policy to resist any law enforcement inquiries with all legal and practical means at our disposal."https://t.co/mgkDwdJRrv pic.twitter.com/qzgWfkNivB— Sarah Emerson (@SarahNEmerson) April 26, 2018
People around the world are relieved to hear he's been caught, though the last attack was nearly 32 years ago.
The DNA database of CA felons helped catch the Grim Sleeper when his nephew was convicted in an unrelated case. I wondered if that’s how authorities suddenly cracked the Golden State Killer’s identity, with familial DNA.— Claudia Koerner (@ClaudiaKoerner) April 26, 2018
So it looks like somebody wanting to know what percentage Irish or German or whatever their ancestors were led to the arrest of California’s most notorious unidentified serial killer— Claudia Koerner (@ClaudiaKoerner) April 26, 2018
But for some reason, it's bringing up some unsafe feelings about ancestry websites.
I work in clinical research & DNA collection is already really complicated (as it should be), it is going to be /really/ interesting how this gets handled— Pierre C. Shadeaux (@Sedna_51) April 26, 2018
for the record, our IRB's DNA policies are strict & would never allow identifiable information to be added to a public database, because doing that is (a) insanely unethical and (b) a great way to get sued and/or fined into the Stone Age— Pierre C. Shadeaux (@Sedna_51) April 26, 2018
but there is also a lot there about the different obligations of medical and research institutions vs private companies using DNA. anyhow I'm sure someone's going to write a really good paper about this & I want to read it— Pierre C. Shadeaux (@Sedna_51) April 26, 2018
But hopefully you're not a serial killer, so you should have nothing to worry about. Right?