Genetic Genealogy Meets the Law

Police use of commercial DNA services

Genetic Genealogy Meets the Law

Saliva has long been important for genealogical research. Years ago, genealogists licked many stamps, conducting much of their research by mail. Today, genealogists still use saliva, except now they spit into a vial that they then mail to a lab. This process is part of a rapidly burgeoning area of research known as genetic genealogy.

Genetic genealogy is the use of DNA to complement traditional methods of genealogical research. Its primary purpose is to provide further evidence of familial relationships. With this evidence, one can identify ancestors or current, previously unknown, relatives.

Genetic genealogy involves submitting a sample of DNA (i.e. saliva) to a commercial DNA service (e.g. AncestryDNA, 23andMe). The service compares the genetic markers of the customer’s DNA with other samples in its database. The service provides the customer with a projection of their likely biogeographical origin or connects them with other customers with significant matches and an estimate of their degree of relationship (e.g. first cousins).

Many commercial services only connect users to their other clients and are limited to the information in their own databases. As well, only paid users can access this information. In order to garner more connections, users can upload their data to an open source service that can compare their data with that of different testing companies. Two of the most popular are GEDmatch and FamilyTreeDNA.

While this new technique caught the genealogy world by storm, it also garnered the attention of law enforcement, particularly in the United States. It is what Blaine Bettinger, an American lawyer and genealogist with a PhD in biochemistry, describes as Investigative Genetic Genealogy (“IGG”).1 IGG is now attracting the attention of Canadian law enforcement, including the VPD.

While law enforcement has long used DNA evidence, it had been restricted in doing so. In Canada, police rely on a national database of the DNA of criminal offenders, governed by the DNA Identification Act. By its nature, there are limited samples for comparison. Furthermore, the analysis is of the cell nucleus, which is of limited assistance in identifying familial relationships. There must be a 100% match for use and it cannot be used for familial searches.

In comparison, commercial DNA services have larger databases and significantly more samples. As well, they usually conduct a “SNP” analysis, which can identify even fairly distant cousins — even those a suspect might not know of.

IGG came to public prominence in the “Golden State Killer” case. Using a DNA sample from a rape test kit, police uploaded data to GEDmatch. (At the time, this was permitted by GEDmatch’s terms of use.) Using the data they obtained, the police worked with a professional genealogist to build a family tree. It is often overlooked that IGG requires traditional genealogy research methods in conjunction with the DNA evidence. The results resulted in the arrest of Joseph DeAngelo. As of March 2020, his case was still pending trial as DeAngelo negotiates a plea deal.

IGG also gained media prominence in BC, in the case of William Talbott. Talbot was convicted in Washington state for the murder of a Saanich couple 32 years ago. This is the first conviction in US case law resulting from IGG. An appeal is pending.

IGG is not without controversy. On one side is the interest in solving crimes. On the other are privacy and Charter concerns, and not only those of an accused or users of commercial DNA services. People who have never even used a genetic DNA service can be connected through IGG techniques. There are also concerns about the diversity of the biogeographical groups represented in the commercial databases.

As a result, many services updated their terms of use. For example, 23andMe developed a “Guide for Law Enforcement” and GEDmatch now requires an opt-in by customers, expressly authorizing police use of their data. There was a significant drop in the commercial DNA testing business due to privacy concerns when IGG came to prominence after DeAngelo’s arrest. These developments have significantly reduced the ability to conduct IGG.

There remains little appreciable law governing IGG in Canada. This will undoubtedly change in the near future. In the US, the Department of Justice developed an interim policy governing the use of IGG by agencies under its authority. IGG will be a growing area of law that the criminal bar will quickly have to adapt to. In the meantime, IGG continues to make waves in popular culture, with pioneering IGG consultant CeCe Moore recently announcing her upcoming television series on the subject.

1 You can watch a February 2020 talk Bettinger gave on IGG at: |

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