5th January 2021
Years ago I undertook study in forensic science. I can tell you it freaked my other half out. In hindsight I feel rather smug about it as it now keeps him on his toes…especially when I tell him that pigs are one of the best ways to get rid of evidence…oh his face!
Forensic science is the collection, preservation and analysis of evidence collated during a criminal investigation. We are familiar with it as a scientific avenue to solving crime from the many criminal based programs that have dominated tv in recent years. The use of finger prints, DNA, blood splatter for example help us narrow down a list of suspects, produce a timeline of events and at times determine cause. Recently in listening to a true NYPD case I came across forensic genealogy which on the face of it seems to be a relatively new but controversial branch for crime scene investigation, adding to the existing tool kit of forensics.
Genealogy is normally associated with uncovering a family tree – beginning with the living and looking for the lost by searching for genetic similarities. According the the UK Government, by early 2019 over 26 million people world wide had given their DNA samples to the likes of 23andme and Ancestry DNA for the express purpose of discovering more about themselves and their wider family.
But how does providing our DNA enable this unearthing? Our understanding of human genetics has advanced notably in recent years due in part to significant and cheaper computing power which has allowed us to unpack the genetic blueprint of every cell in our body. This is the sequencing of the the human genome that was ‘completed’ in April 2003. I hesitate over the use of the word completed because there is a great deal we do not understand about DNA; we are still learning what much of it does and how it governs who we are. However research shows that we share approximately 50% of our DNA with a parent reducing for more distant relatives. For example with a third (related) cousin we share, on average, only around 0.8%. This means we share ‘longer stretches of DNA with our relatives than with unrelated individuals’ (23andme.com) and we now have tools to establish this more accurately.
Forensic genealogy is described in many ways but the basic premise is starting with the ‘deceased and looking for the living’ (www.recordclick.com). When researching I could not precisely pinpoint the practical activities that it encompasses however according to Colleen Fitzpatrick who published a book on the subject, it can entail:
- Examination of photos to pinpoint time and places
- Data mining into family history and
- Genetic analysis of DNA to discover matches, non matches, ancestors, branches of a family.
It is this last activity, above the normal analysis of DNA, that has invited controversy in the field of law enforcement.
Utilising forensic genealogy, the DNA found at a crime scene (usually of the perpetrator) is compared to thousands of other DNA samples providing a list of people related to this unknown suspect however distant. Parabon Nanolabs (a US company active in this area), take this data melding it with official birth, death, marriage, mobile phone records for example and narrow down the the list of suspects into potential perpetrators of the crime for whom the time, place and DNA fit (sciencefocus.com). They are even able to produce CGI images of a suspect using their DNA analysis.
In the USA, many cold cases are being re-visited utilising this approach. The main spur to usage was the identification and arrest in April 2018 in California of The Golden state killer who was responsible for 12 killings, 51 rapes and more than 120 burglaries between 1974 to 1986. This sounds incredible when you consider that up to the point of identification the police had considered over 8000 suspects. Can you imagine the labour intensity of such a process without speedy techniques to narrow that list down.
So what’s the issue? This is the problem in the USA. The thousands of DNA samples that are compared are not those held on a police database but have been given by the public to the online genealogy companies to find relatives or understand their own DNA composition. Legal and ethical considerations rear up. Is it right that I give my personal data for one purpose and it is used in a way I did not specifically give permission for – even if that purpose is ultimately for the good of society? What if the results are vague, augmented by co-incidences, how will I be absolved – where does the burden of proof lie? What of the trauma my complicit agreement might cause unnecessarily on those around me?
We are in a slightly different situation in the UK as law enforcement has access to one of the largest DNA libraries in the world enabled to collect DNA data from an individual convicted of a recorded crime and retain it indefinitely. In September 2020 the UK Biometrics and Forensics Ethics group published a report on the use of genetic genealogy noting the success in the USA but wary of making use of wider sources of DNA data for ethical reasons.
Even here in the UK, this seemingly legitimate retention of DNA data has activists worried about the big brother nature of such a database, concerned that our DNA may be more of a public asset than we realise. I for one welcome this discussion as part of a wider privacy debate. We are still resolving the boundaries of ownership of our online personal data with regards to Facebook, Google, street cameras for example, generating many conflicting views over how it is used, manipulated, sold. DNA data in the hands of Government does not seem to carry the same potential to be used for malign purpose as other personal data but perhaps I’m being naive?
Still, this doesn’t stop me frightening my other half with my new found forensics knowledge…..its rather fun keeping him on his toes…..
Curiosity and the rascal 