Genetic genealogy technique used in Christine Jessop cold case comes with privacy concerns, warns expert

However, she told The Current‘s Matt Galloway she worries about the trend toward “bulk surveillance” — the use of “relatively indiscriminate technologies” to look through thousands of people in search of one particular person. She cited facial recognition, which has the ability to scan and identify everyone in a space, as one example.

“Essentially what it is is a fundamental change to the social contract in a democracy where we expect to be free of scrutiny by the state unless there’s a reason to believe that we’re a danger to society,” said McPhail. “And with these [kinds] of bulk methods of surveillance, everyone is under a low-grade suspicion all the time.”

Last week, Toronto police announced they had used genetic genealogy to identify the man they believe murdered nine-year-old Christine Jessop in 1984. Genetic genealogy combines DNA analysis with genealogical research by matching a sample to a database of DNA to determine a familial relationship and identify a likely suspect.

In 2018, investigators identified Joseph James DeAngelo as the Golden State Killer by comparing DNA from one of the crime scenes to online genetic profiles.  He pleaded guilty this year to 13 murders and 13 rape-related charges under a plea deal, and was handed several life sentences.

A similar technique helped solve the cold case of two B.C. teens who were murdered in 1987 during a trip to Seattle.

‘Buyer beware’ of terms of service, says expert 

McPhail said it’s good that families like Jessop’s have closure, thanks to the help of genetic genealogy. However, many people who use genealogical or ancestry matching services may not realize what they are consenting to when they sign up to use them.

“Some [services] don’t voluntarily co-operate with police or let them upload data, and others do,” said McPhail.

“So in some ways it’s buyer beware. But it’s buyer beware in an incredibly complicated environment where the consequences for us clicking the opt-in … are huge — and for many people, really unknowable.”

One of those risks includes being misidentified as the suspect of a crime, and the “anguish” that could come with that, she said. 

Another implication is that when you consent to using a genetic database, you’re also consenting “for all those who came before you, your children, their unborn children, and you know, forward into the future,” said McPhail.

“So how reasonable is it to ask one individual to consent to the exposure of that many others who are connected to them?”

Balance between privacy, justice

Anthony Redgrave, a forensic genealogist who worked with Toronto police on the Jessop case, says he believes a middle ground can be struck when it comes to using genetic genealogy to solve cold cases, while also respecting people’s privacy.

“There are very clear terms of services on the sites that we use and they should be adhered to,” he said. 

There needs to be a more public education aspect to what it means to opt in to law enforcement matching.– Anthony Redgrave, forensic genealogist

Redgrave also said the science behind the technique is “incredibly reliable.” Once he finds a candidate for identification, law enforcement officials then confirm that candidate through another form of DNA testing, fingerprints, dental records or interviews with family, he explained.

He added that he thinks wrongful identification can be avoided through direct communication between experts like himself and law enforcement.

However, he agrees there is room to make the terms for using such genealogical services more clear.

“There needs to be a more public education aspect to what it means to opt in to law enforcement matching,” said Redgrave. “And I think there also needs to be more education for departments on how to use it appropriately and fairly.”

Written by Kirsten Fenn, with files from CBC News. Produced by Julie Crysler and Alex Zabjek.