In the past year genetic genealogy has gained momentum as a tactic to solve violent crimes and identify human remains. Most of the cases solved had been cold for years, when all other investigative efforts had proven inadequate. In genetic genealogy the potential exists to close previously unsolvable cases where biological evidence is available; whether that be to exonerate the innocent or identify the perpetrators.
Genetic genealogy investigations depend on DNA databases consisting of DNA profiles derived from biological samples sent to private genealogy labs. Samples for DNA profiles are voluntarily submitted to genetic testing labs used by companies like 23andMe, AncestryDNA and Family Tree DNA. Once a unique DNA profile is created, the individual who provided the sample has control over what is done with it. It can be kept private, made public, downloaded, shared to public databases and can even be completely deleted. So for genetic genealogy to be effective, there must be public support and participation.
As with all new technology and methods that come along, there are skeptics and critics. One of the main areas of critique is that some feel police are violating the privacy of individuals by accessing and using voluntarily submitted profiles to implicate people without probable cause. However, unless someone actually left a biological sample on the victim of a crime, they are only being implicated as a relative and possible lead to a suspect and not necessarily a conviction.
Americans are typically very apprehensive when it comes to privacy issues and don't freely relinquish privacy rights. Yet lately it seems that the majority of society is in favor of doing just that. We have decided that safety and justice are worth the trade-off. In actuality this isn't a recent phenomenon. DNA dragnets have been a tool for some law enforcement agencies since the forensic value of DNA was first realized.
In 1986, police in Narborough, Lecestershire were investigating the rape and murder of 15 year-old Dawn Ashworth. They believed the perpetrator had also raped and murdered 15 year old Lynda Mann two years prior. A 17 year old boy, Richard Buckland, quickly confessed to Dawn's murder. Richard had learning disabilities and while he confessed to Dawn's murder several times he also recanted his confession. He also claimed he had no involvement in Lynda's murder. Richard was arrested for Dawn's murder but police were skeptical.
Police enlisted the help of geneticist, Alec Jeffreys. Alec accidentally discovered that DNA cells attached to photographic film would produce sequences of bars that were unique to each person whose sample had been developed. In fact, the individuals could be precisely identified using their DNA cells and these DNA cells could also be used to prove kinship. Jeffreys had been using this technique to prove to their immigration office that some children tested were the children of British parents; gaining them British citizenship.
Narborough police called upon Jeffreys to analyze blood taken from Richard Buckland to determine if he was in fact guilty of the crime he confessed to. When Buckland's DNA was compared to the crime scene evidence taken from Dawn and Lynda, Richard Buckland became the first person proven innocent of a crime by DNA fingerprinting. It was clear that Buckland was not her rapist but it was also clear that Dawn and Lynda were raped and murdered by the same man.
The police were now left with two unsolved murders of 15 year old girls and they had no viable leads. What they did have was biological crime scene evidence from the two murders and the capability to weed out any future suspects by obtaining their DNA.
Police identified members of the local male population that were within the probable age range of the murderer and sent them letters asking for blood samples to be used in the investigation. Surprisingly, they were able to obtain thousands of voluntary samples. Some were hesitant to give their blood to police but the desire to identify and remove the perpetrator from society was enough to compel thousands of samples. Unfortunately none of the samples were matches.
Once again police were left with no suspects as the population had been freed of suspicion because there were no DNA profiles that matched the murderer. Then a local man confided to some friends that he had been paid to go to one of the sites where police were collecting blood samples from and give blood in another man's name. The man who had given blood and the man who paid him to do it were both taken into police custody.
Colin Pitchfork paid one of his coworkers to give blood in his name. After being taken into police custody Pitchfork confessed to raping and murdering the two teen girls. DNA evidence collected from the real Colin Pitchfork proved him to be the rapist and murderer. Pitchfork had been questioned earlier in the investigation and cleared as a suspect.
Many people who support the use of genetic genealogy in police investigations believe that anyone who opposes its use has something to hide. That was certainly the case with Colin Pitchfork. It was his attempt to dodge the DNA screening that ultimately led to his incrimination. Mass DNA screenings have since been conducted by police in attempt to solve murders.
Public genetic genealogy databases provide the public a means to voluntarily submit their DNA and allow it for use in police investigations. Voluntarily submitting DNA samples to genetic genealogy databases is much more efficient and less invasive than past mass screenings conducted by law enforcement. Owners of profiles will never even be contacted by law enforcement unless further information is needed concerning a relative.
GEDMatch has recently changed its privacy settings disallowing police use of individual profiles by default. Unless users manually opt-in to allow the police access to their genetic information it can not be used in investigations. Family Tree DNA will allows law enforcement to upload profiles but they must gain written permission on a case-by-case basis and permission is only granted for rape, murder and unidentified human remains.
Genetic genealogy has been used to identify the perpetrators of over 60 violent crimes and identify decades old human remains in the past year. These are just the cases that have already been made public. Previously unsolvable cases can continue to be solved but it will require that more people submit their samples and allow them to be used in investigations.