Broad adoption of forensic genetic genealogy (FGG) in criminal investigations depends on good governance and on success in the courtroom. When FGG helps identify a suspect, the police, scientists and/or genealogists need to explain how they arrived at that person’s name. Prosecutors need independent evidence connecting that person to the crime. Both groups should consider the threshold(s) that a court will assess whether the steps they took and the results they obtained are admissible.
In the United States, many FGG investigations have reached the courtroom, and Othram has contributed to many of them. Our work helped identify the man who murdered Carla Walker in Texas and supported the prosecution of a decades-old homicide in Queens, New York. Canadian agencies have also used FGG successfully. What has been harder to find in Canada is a detailed judicial account of why a particular investigation endured a challenge under the Canadian Charter of Rights and Freedoms. R. v. King provides one.
From a Preserved Sweater to a DNA Warrant
On April 14, 1995, a 16-year-old girl was walking home across a Toronto schoolyard when a stranger threatened her with what appeared to be a handgun and sexually assaulted her. She ran home, told her mother, and later showed police where the attack had occurred. Ontario’s Centre of Forensic Sciences developed a traditional DNA (i.e., short tandem repeat or STR) profile from semen on her sweater. Comparisons ruled out several people, a national DNA database search yielded no leads (even though the ultimate identified perpetrator had been convicted previously of sexual assault), thus the attacker remained unidentified for nearly three decades.
In 2023, Othram used Forensic-Grade Genome Sequencing® to develop a single nucleotide polymorphism (SNP) profile from the preserved evidence. Searches of GEDmatch PRO and FamilyTreeDNA identified a large number of possible relatives. Toronto police spent hundreds of hours tracing those relationships through public records before identifying Leslie Richard King as a person of interest.
Officers later recovered a cup that King had discarded. The Centre of Forensic Sciences compared DNA from the cup with the original crime-scene profile using conventional STR testing. That result helped police obtain a warrant for a sample of King’s blood. The laboratory found that the DNA results were more than one trillion times as likely if King was the source of the crime-scene DNA as if an unknown person unrelated to him was the source.
Why the Judge Upheld the Investigation
King challenged both the genealogy search and the collection and testing of the cup. Police had carried out each step without a warrant. The defense argued that both infringed his right under section 8 of the Charter to be secure against unreasonable search and seizure. Because police relied on those steps to obtain the blood sample warrant, King asked the court to exclude the resulting DNA evidence.
On August 7, 2026, Justice S. Boucher of the Ontario Superior Court of Justice dismissed the challenge. Three parts of the reasoning are especially relevant to future cases.
- Police could explain why they turned to FGG and why they used this sample. They were investigating a serious violent offence. Conventional DNA comparisons and a search of the national DNA databank had produced no suspect. Police lawfully held the evidence from the survivor’s sweater. The judge accepted that King had a personal privacy interest in information about his extended family. Even so, the circumstances in which the biological material was left on the survivor’s clothing supported using its identifying features to determine who deposited it, including by tracing family connections.
- The court examined what police actually learned about other people. The donors who voluntarily uploaded their SNP profiles into genetic genealogy databases and were identified as relatives of the source of the crime scene evidence had opted in to law-enforcement matching. Police received information about possible relatives and how much DNA they shared with the unknown person. The search disclosed no medical or behavioral traits. King’s own profile was in neither database and his name appeared in none of the family trees users had shared. Detectives had to establish those connections through publicly- accessible records. They kept their working tree private and attached the documents supporting its branches. Those details helped the judge assess the degree of intrusion on privacy and understand how investigators reached King.
- Police independently tested the lead and disclosed how they obtained it. By the time officers collected the cup, they had specific grounds to suspect King, including his family connections, age, and where he had lived. The judge found that King had abandoned the cup in a public garbage can. Only the original crime-scene sample underwent genealogy testing. The cup underwent a conventional STR profile comparison. When police sought authority to take a blood sample directly from King, they told the issuing judge about both the genealogy research and the cup. Justice Boucher found no Charter breach at either step. The judge also concluded that the blood evidence would remain admissible even if either step had breached the Charter.
On October 29, 2026, Justice Brees Davies found King guilty of sexual assault. The Crown had charged him with sexual assault with a weapon, but the evidence did not establish beyond a reasonable doubt that the object used was a firearm. The survivor addressed the court that day, 31 years after she first reported the attack.
What Canadian Police and Prosecutors Can Take From King
For a police service reviewing an unsolved case, King gives investigators concrete questions to address early on in an investigation. Why is FGG appropriate for this case? What lawfully held sample can be tested? Who has agreed to law-enforcement matching, and what information will investigators receive? Documenting that record from the outset also gives the Crown what it needs later to explain the search, account for the privacy interests of relatives, and show how police independently verified the lead. Ontario’s privacy commissioner has published guidance that agencies can draw on when making those decisions.
Justice Boucher confined the ruling to the facts of this investigation but expressly recognized room for future use: “There is scope, however, for IGG to be deployed in a constitutionally compliant manner pending any decisions to regulate the practices around IGG.” The court used investigative genetic genealogy, or IGG, for the technique we call FGG.
That conclusion is encouraging for Canadian agencies with preserved evidence and no suspect to compare it to. When another investigator opens a file like the Toronto case, there is now an Ontario decision explaining why police could pursue a family lead without first obtaining a genealogy warrant, how they protect the people whose information made that lead possible, and how the evidence they develop could be used in court.
