By: Derek Reigle

Dna, Biology, Medicine, Gene, Microbiology, Analysis

The Golden State Killer, also known as the East Area Rapist or the Original Night Stalker infamously murdered over a dozen people and raped more than fifty victims from 1976 to 1986.[1] Despite these horrible crimes, the identity of the Golden State Killer had eluded justice for decades.[2] However, on April 24th, 2018, investigators solved this cold-case and arrested Joseph DeAngelo, a 72-year-old man and former police officer, as the Golden State Killer.[3] The police broke open the case using the tactic controversial of familial DNA Testing.[4]

The actual science of familial DNA testing is complicated, but the concept is simple. Are you familiar with websites such as or These websites allow one to submit your DNA through a kit that can be sent to one’s house.[5] These kits only require a saliva sample.[6]After your DNA is collected and analyzed, these websites can reveal a staggering amount of information about oneself.[7] One can learn where your ancestors are from, whether one has certain genetic predispositions that can be passed onto one’s children, or even how one’s genes affect your caffeine consumption.[8] Furthermore, these DNA results can be uploaded to other websites such as that can reveal even more comprehensive information about one’s genealogy.[9]

An additional key aspect of these DNA tests is that they allow you to view family members that were known, or previously unknown.[10] This can be done by identifying certain genetic similarities in one’s genealogy.[11] Naturally, this ability to track down long lost family has amazing benefits that can allow one to learn more about their family.[12] However, the ability to track down forgotten relatives has opened the door for law enforcement to identify criminals.[13]

The Golden State Killer was caught because a member of his family had uploaded their genetic DNA results to[14] Police had DNA from the crime scenes from the 1970 and 1980’s but had no way to identify whose it was.[15] Thus, they uploaded this DNA to and were able to find out who the great-great-great-grandparents were of the unidentified DNA.[16] After crafting 25 family trees, using incredibly detailed historical research, investigators were able to zero in on Joseph DeAngelo.[17] After identifying DeAngelo as a suspect, police recovered a discarded object by DeAngelo that has his DNA on it.[18] Law enforcement was then able to match the DNA between DeAngelo and the Golden State Killer.[19] DeAngelo now faces thirteen counts of murder.[20] Prosecutors have announced that they will be seeking the death penalty.[21]

This is an amazing story that testifies to the awesome power that familial DNA testing has to find and locate unknown criminals.[22] However, this case raises several additional questions that will have vast legal ramifications as genetic identification techniques only become more advanced because of technology’s unique ability to consistently improve over time.[23]

Across America, civil liberty groups like the ACLU have challenged familial DNA testing as invasive of an individual’s privacy rights.[24]  Should a family member consenting to have their genetics analyzed reveal information of a third party that has not consented? Further questions regarding the values of our criminal justice system such as fairness, equality and deterrence of such a futuristic law enforcement technique are now being raised., and have all responded to concerns about privacy and the use of genetic material to aid law enforcement by updating their standards of privacy and releasing a variety of statements.[25] Generally, search warrants are required to access this information on these websites.[26]

Familial DNA testing is not going away and will continue to be used by law enforcement.[27] In order to better assess the benefits and consequences of this unique crime-fighting technique, one should know the story of the Golden State Killer.

[1]  See Hilary Brueck, The Suspected Golden State Killer was Finally Caught Because his Relative’s DNA was Available on a Genealogy Website, Business Insider (Apr. 27, 2018),

[2] See Id.

[3]See Id.

[4] See Associated Press, The Latest: Investigator: Free DNA Website Helped Crack Case, Business Insider (Apr. 27, 2018),

[5] See How does AncestryDNA Work? An Inside Look at The Process, Ancestry (last visited Oct. 20, 2019),; 23andMe, 23andMe, How It Works!, Youtube (July 2, 2018),

[6] See Id.

[7] See Id.

[8] See Id.

[9] See GEDmatch.,Your DNA Guide, (last visited Oct. 20, 2019),

[10] See Brueck, supra note 1.

[11] See Id.

[12] See Id.

[13] See James Rainey, Familial DNA puts Elusive Killers Behind Bars. But Only 12 states Use It., NBC News (Apr. 28th, 2018),

[14] See Brueck, supra note 1.

[15] See Justin Jouvenal, To Find Alleged Golden State Killer, Investigators First Found his Great-Great-Great-Grandparents, The Washington Post (Apr. 30, 2018),

[16] See Id.

[17] See Id.

[18] See Id.

[19] Breeanna Hare and Christo Taoushiani, What We Know About The Golden State Killer Case, One Year After A Suspect Was Arrested, CNN (Apr. 24, 2019),

[20] See DA Will Seek Death Penalty Against Golden State Killer Suspect Joseph DeAngelo, CBS Sacramento (Apr 10, 2019),

[21] See Rainey, supra note 13.

[22] See Id.

[23]See Alison E. Berman and Jason Dorrier, Technology Feels Like It’s Accelerating — Because It Actually Is, Singularity Hub (Mar. 22, 2016),

[24] See Shankar Narayan, Familial DNA Searching: Troubling Civil Liberties Challenges, NWSidebar (June 20, 2018),

[25]See Eric Rosenbaum, 5 Biggest Risks of Sharing Your DNA with Consumer Genetic-Testing Companies, CNBC (June 16, 2018),

[26] See Colin McFerrin, DNA, Genetic Material, and A Look at Property Rights: Why You May Be Your Brother’s Keeper, 19 Tex. Wesleyan L. Rev. 967, 998 (2013).

[27] See Justin Poulsen, Your Relative’s DNA Could Turn You Into a Suspect, Wired (Oct. 13, 2015),

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