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How Big Data Helped Track The Golden State Killer!

For over a decade, between 1974 and 1986, Joseph James DeAngelo inflicted gruesome acts of terror in his crime sprees. These vicious crimes included 13 murders, 50 rapes and over 100 burglaries in California aka the Golden State. While he went on a rampage in various parts of California from Sacramento to the south of Los Angeles, he was known by a variety of names like “Visalia Ransacker”, “East Area Rapist”, the “Original Night Stalker” and the most notorious of them all, “the Golden State Killer”. Unfortunately, it took about 40 odd years for the law enforcement agencies to realize that all these nicknames belonged to one man alone, Joseph James DeAngelo.

What helped them nail him? Not stakeouts or fingerprints or cell phone records but data collected from a popular genealogy website!

Major Breakthrough In The Golden State Killer Case

The major breakthrough in the case of the golden state killer happened in 2011. According to a news report in the Times, the advent of DNA technology had helped authorities nail the serial offender.

After struggling for years to find whom the DNA from the crime sites of the golden state killer belonged to, investigators from the Sacramento County Sherriff’ Department confirmed that they got crucial information from genealogical databases that the public uses to track their relatives and ancestry.

The Link Between Big Data And Geneology Websites

Publicly available genealogy databases have become the one-stop destination to solve cold-case crimes. When people submit their information on to these sites, investigators have been successfully able to use this data to identify victims, killers and missing people in several cases. The technique used by investigators is a genomic analysis type called long-range familial search. Researchers can match an individual’s DNA to distant relatives as far as third cousins too.

Using this revolutionary analysis, it has been estimated that an average person in the U.S. has about 850 third cousins. Websites like AncestryDNA and 23andMe have the maximum number of customers curious to track their ancestry. Similarly, DNA data from the Golden State Killer’s crime scenes were submitted to GEDmatch database.

When coincidentally, a distant third cousin of the killer used the same platform to know more about their ancestry, investigators were able to narrow it down from there using family trees, demographics, and other clues.

The investigators found 100 potential suspects who fit the age profile of the killer. With the help of well-trained genealogists, it was confirmed that the suspect would have a blue eye color and would be more prone to premature baldness. Eventually, the serial killer, Joseph James DeAngelo, was finally arrested and charged for his ghastly crimes in April 2018.

The Arrest Of The Golden State Killer: A Gray Area In The Digital Age

When the case of the Golden State Killer played out on mainstream media earlier this year, it raised many a question in people’s minds. Anytime you upload sensitive information on a public database or platform, your data is vulnerable to being exploited.

In every nation, law enforcement agencies have the legal right to take information from these genealogical databases even if it doesn’t seem ethically right for many. When you or your relative uploads a DNA sample, you are potentially putting your familial pedigree in the open. Websites that work with genealogical data assures customers that their data will remain safe. However, they also claim that in the event of an investigation, they would have to provide access to their users’ data to the law enforcement officials.

The arrest of the Golden State Killer is not only a giant leap for crime prevention and law enforcement but also a typical example of legal and ethical conflict in the age of Big Data.

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A Lifelong Learner.

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