The recent capture of the "Golden State Killer" has become one of the biggest breakthroughs in American criminal history in years. Amazingly, 72-year-old former police officer and main suspect Joseph James DeAngelo was caught because investigators used a genealogy website.

According to reports released by the Associated Press, DeAngelo, despite being a methodical killer, left DNA evidence all over his crime scenes. During his heyday as an alleged serial killer between 1976 and 1986, DNA testing was in its infancy. Now, thanks to major advancements in forensic science, FBI agents and California law enforcement officials managed to match DeAngelo's DNA with the DNA samples taken from the old crime scenes.

At first, the FBI and California investigators used his DNA to create a profile. Unfortunately, no suspect matched this profile for decades. Then, investigators logged onto GEDMatch.com, a research database frequently used by genealogists. According to the Mercury News in San Jose, California, GEDMatch.com was able to provide DeAngelo's information because it fit with the DNA profile.

Privacy fears

Once word spread that GEDMatch had been used to find the "Golden State Killer," website operator Curtis Rogers sent out a response claiming that users of the open-source site should be aware that their information could be viewed and used by law enforcement agencies. "While the database was created for genealogical research, it is important that GEDMatch participants understand the possible uses of their DNA, including identification of relatives that have committed crimes or were victims of crimes."

Rogers also claimed that no law enforcement agency had contacted his company about their investigation.

Recluse

After DeAngelo was arrested earlier this week, his neighbors in the Sacramento suburb where he lived for years, were reported by CNN to describe him as a "recluse." DeAngelo did not often interact with his neighbors and was known to own several firearms. In 1964, DeAngelo completed basic training for the US Navy in San Diego and served onboard the USS Canberra during the Vietnam War.

After leaving the service, DeAngelo worked as a police officer for the cities of Exeter and Auburn, California. He was fired from this job in 1979 after he was caught shoplifting a hammer and dog repellant from a local store. Given the span of DeAngelo's crime spree, it is very likely that he committed some of "Golden State Killer" murders while he was a working police officer.

Following his dismissal in 1979, DeAngelo was employed as a mechanic for the California grocery chain Save Mart. He held this job for twenty-seven years, and only retired in 2017.

For ten years, between 1976 and 1986, the "Golden State Killer" committed at least fifty rapes and twelve murders in ten different counties in California. During this time, some detectives did theorize that the serial killer had some law enforcement training.