The capture of the Golden State Killer in April 2018 drew attention not only because his crimes were committed decades earlier, but for the way he was identified. Law enforcement used familial searches of DNA databases to track down the killer. Familial searches are based on the idea that family members have similar DNA. Therefore, even if a match isn’t strong enough to identify the criminal it may be enough to obtain a warrant for the identity of the relative.
The CODIS database, historically used by law enforcement, stores a limited amount of DNA data. However, when this information is linked to records in consumer DNA databases, it is possible to more accurately link a person’s relationship to others. Databases such as GEDMatch and FamilyTreeDNA allow consumers to upload their genetic profiles. Most people who do so are hoping to make family connections and build out their family trees. However, law enforcement has also discovered these databases and is using them to identify criminals.
DNA databases are not only used to find criminals, they are also useful in identifying unknown victims. The DNA Doe Project helps to identify Jane and John Doe crime victims, often in cases going back decades.
AncestryDNA and 23andMe do not allow law enforcement searches of their databases and 23andMe says that they will “use all legal means to safeguard our customers’ data.”
Genetic genealogy is not enough evidence to make an arrest, but it is a lead that can send law enforcement on the trail of identified suspects. The next step is to obtain genetic material from the suspect (often pulled from their trash) and comparing the DNA to that found at the crime scene.
There are privacy concerns with these searches because even persons who have not uploaded their DNA to a public database may be identified because a distant relative did. And it is not only consumer-provided DNA samples that can be used this way. Natalie Ram of the University of Baltimore, Maryland says that in many places police may legally take DNA samples from persons who are detained or arrested, but not charged with a crime. So, it is possible that DNA, for example, from a protester who is taken into police custody could be used later to track down their third cousin who is suspected of a crime.
Even people who have never committed a crime may be uncomfortable with the availability of genetic information in publicly accessible databases. However, law enforcement does not have carte blanche to search DNA profiles. For example, their searching of the FamilyTreeDNS database is limited to profiles who are a genetic match to crime scene samples. And no one (not police or other consumers) has access to individuals’ raw genetic DNA.
So, should you be worried about the security of your DNA data? Forensic genealogist Melinda Lutz Byrne says that although no information on the internet is completely secure, she doesn’t know why anyone would want it. “They want your credit card more than your DNA,” she says.
