Genealogy websites helped track down elusive Golden State Killer

27 Apr 2018

DNA from an online database helped catch the Golden State Killer. Image: Henrik Dolle/Shutterstock

Joseph James DeAngelo, the alleged Golden State Killer, was apprehended using DNA from a genealogical website.

The man suspected to be the Golden State Killer (also known as the East Area Rapist and the Original Night Stalker), Joseph James DeAngelo was arrested earlier this week in Sacramento, California.

The Golden State Killer was a notorious serial rapist and murderer who terrorised the entire state of California for years in a period of time before mobile phone towers and social media, and it looks like modern technology is the reason DeAngelo was apprehended this week.

The Sacramento Bee reported that he had been tracked down using genealogical websites containing genetic details from a relative. The district attorney’s office for Sacramento confirmed this and said DNA from one of the crime scenes decades ago was compared to genetic profiles available online through a variety of websites, which allow people to discover their genetic heritage and research their family background.

The investigation was a painstaking process, but investigators zeroed in on DeAngelo after a match was found. They found he had lived in areas where the attacks had taken place and was in the right age range, according to district attorney Steve Grippi.

DNA was obtained from something discarded by DeAngelo and the crime lab then began testing the material.

Arrested after decades

DeAngelo was arrested outside his home on 24 April on two charges of murder for the February 1978 killings of young couple Katie and Brian Maggiore in the Rancho Cordova area and is expected to face charges in 12 cases of homicide in Sacramento, Orange County, Santa Barbara and Ventura. In total, the Golden State Killer is said to have killed 12 people, raped at least 51 and burgled hundreds of home from 1974 to 1986.

On Wednesday (25 April), Sacramento county sheriff Scott Jones told press that DeAngelo had worked for the Auburn police department in California from 1976 to 1979 and was let go after stealing a hammer and dog repellent from a pharmacy in the neighbourhood of Citrus Heights. He also worked as a police officer in the town of Exeter near Visalia from 1973 to 1976. A criminal was active during this time known as the Visalia Ransacker, who burgled many homes in the area.

In terms of privacy, both and will provide information to law enforcement.

Tiffany Li, a tech lawyer and resident fellow at the Yale Information Society Project, tweeted: “Reminder: when you give your DNA data to companies like or 23andMe, you give up not only your own genetic privacy, but that of your entire family.”

Privacy worries

Some experts are concerned that the ability of law enforcement to create a genetic profile of someone while seemingly bypassing the standard criteria of obtaining a search warrant or a subpoena. 23andMe, and MyHeritage have all denied their involvement in the case.

A warrant is not required if a company freely provides user data. While seeing a serial killer be apprehended after many decades is undoubtedly a positive, the methods involved do raise questions about how we share information with companies, and the implications of sharing that data.

Ellen Tannam was a journalist with Silicon Republic, covering all manner of business and tech subjects