One of the leading U.S. forensic experts, who served as the primary DNA specialist prosecutor in O.J. Simpson's murder trial, says Canadian agencies are doing victims a disservice by using a potentially misleading DNA technique, instead of a surer method to identify suspects. But it's a method that does come with some privacy risks.

"If anybody from Canada is ignorant on the subject in forensic leadership or in law enforcement, they need to get replaced with someone who knows what's going on. It's a disservice to the victims and their survivors that this isn't as pressing a subject," forensic DNA consultant Rockne Harmon told CBC News, speaking by phone from his California home.

Harmon spent 33 years as a prosecutor until his retirement in 2007 as senior deputy district attorney of the Alameda County District Attorney's office.

Forensic expert Rockne Harmon says it's time for Canada to update its DNA Act, and allow law enforcement to use better techniques. (Supplied)

In 1995, he was the DNA specialist prosecutor in the case of the People of California vs. O.J. Simpson, and he's devoted the decade since his retirement to advising law enforcement agencies on the latest DNA forensic technologies.

When he saw that Calgary police paid $3,600 to have a company create a composite sketch of a woman using her DNA earlier this year, he was left shaking his head.

Calgary police hired U.S. biotech company Parabon NanoLabs after they had run out of leads on a case.

On Christmas Eve 2017, a newborn girl was found dead in a parking lot in the northwest Calgary neighbourhood of Bowness.

Evidence at the scene suggested the mother might have been in medical distress, so police turned to Parabon, which created an image of what the baby's mother could look like with a program called Snapshot.

The composite, which both police and Parabon stressed was simply an approximation, was released in order to solicit tips from the public.

The sketch of a woman was created through a process called DNA phenotyping. It shows what Parabon says is a possible likeness, at about age 25, of the mother of a baby found abandoned in a northwest Calgary dumpster on Christmas Eve 2017. (Calgary Police Service)

The program used the suspect's genetic evidence to produce a report that includes the person's likely hair colour, eye colour, face shape and ancestry, among other traits, based on genotype data.

"Why did they pick Parabon? Because it's easy," said Harmon. "I can't give you a good answer. Ignorance, laziness."

The lab charges $3,600 US for each profile, crafted from statistical models that correlate genes with physical traits, to create the composite image.

But a University of Calgary researcher who studies the significance of phenotypic variation and variability said the portraits created are "not just potentially useless but even potentially misleading."

"I think the evidence is not there to support the use of this technique … we know very little about the genetic variants that determine the shape of the face or features like the shape of your nose or the shape of your cheeks or the height of your face, or the width," said Benedikt Hallgrímsson.

Hallgrímsson said the genetic markers that determine facial features are "extraordinarily complex," and that if he had to put a number on it, he would estimate that scientists could predict skin colour with 25 per cent accuracy — and that the precision of predicting a person's face shape would likely be much lower.

Snapshot composite images are shown next to the suspects who were eventually arrested. (Snapshot DNA Phenotyping)

"It can be a sorting-out tool and that's all that it can be. I'm not saying it's totally bogus, but it's certainly not as worthwhile as the cops make it sound," Harmon said.

"What good is it if nobody ever saw the guy? Yes, you get a picture. But then what did you do with it?"

Calgary police wouldn't comment on the use of the technique and referred all questions on the subject to Parabon Labs.

Ellen Greytak, the director of bioinformatics at Parabon, told CBC News in February that the composite is meant to simply be a general idea of what the person might look like, not a photo-realistic image.

The technology has also been used by police in Vancouver, Windsor and Sudbury. It was used in Florida in an attempt to solve the murder of a pair of Toronto vacationers.

None of those cases have been solved.

The RCMP declined an interview with CBC regarding the forensic techniques the agency uses, but said in an emailed statement that the National Forensic Laboratory Services (NFLS) doesn't currently use DNA phenotyping, but it is exploring the technique's "potential for future scientific investigative purposes."

What Canada isn't doing

Instead of using phenotyping to create portraits — a technique that has no peer-reviewed evidence to support it — Harmon said Canadian agencies need to look to their neighbours to the south and use a technique called familial DNA matching.

The technique works like this. Canada has a national database that holds DNA of criminal offenders. When evidence is found at a crime scene, one of the first things law enforcement agencies do is search that database. But, if it doesn't turn up a copy, police can then search for close relatives — parents, children or full-siblings — that would have shared alleles with the original DNA sample.

"It's possible to use it on any kind of case that could be solved by DNA," Harmon said.

In April, U.S. law enforcement used an open-source genomics database to nab a suspected killer that had been wanted since the 1970s.

DNA Act limits what law enforcement can do

So why did Calgary police spend thousands on a technique that experts say is misleading instead of trying a familial DNA search?

While Calgary police wouldn't comment on their use of Parabon's technology, they did say why they couldn't use familial searches: Canada's DNA Identification Act prohibits it.

A public affairs spokesperson told CBC that Canada is one of the only western countries not to allow familial DNA typing, even though it has been used to solve dozens of cases in the United States and around the globe.

"Jurisdictions that currently do use familial searching do so either on the basis of explicit legislative permission, or in some cases, more disturbingly, in the absence of any legislation explicitly prohibiting it," Patricia Kosseim, the senior general counsel at the office of Canada's privacy commissioner, said during a 2015 speech at the Canadian Institute on the Administration of Justice.

"It's true than no law has explicitly authorized the use of familial DNA searching … the question you ask is, 'Does familial DNA searching achieve the statutory purpose for which the database was created?' We're not diagnosing cancer or doing insurance risk or anything like that," said Harmon.

Police could potentially use DNA from direct-to-consumer genetic testing companies or open-source databases that people have chosen to contribute to in Canada, under the country's privacy laws, but it's not clear if they have done so.

The RCMP sent the following statement when asked for comment on whether or not the agency is using the latest forensic techniques:

"The use of science to serve justice is constantly changing, and the RCMP NFLS continue to invest considerable time and efforts to review new scientific processes and technologies. NFLS collaborates with partners from other forensic organizations to ensure that such processes have a solid scientific foundation and are valid and reliable for specific forensic applications."

The technique does raise some privacy concerns.

A paper published in October in Cell, a leading peer-reviewed biology journal, found there are privacy risks for those that may have no idea their relative's DNA is entered into databases, either commercial or otherwise, as their relative's genes could expose information about both their identity and health.

Progress on forensics seemingly stalled

Canada's been looking at implementing familial searches for a decade, but the process appears to have stalled.

Researchers in a 2009 parliamentary publication noted that the size of Canada's databank could be a hindrance, as less than 0.5 per cent of Canadians at the time were profiled — the bank only includes Canadians with a criminal background.

It doesn't always need the database to work. Familial genetic similarities were used to solve a 2002 Alberta murder, when relatives of the suspect voluntarily submitted their DNA samples to be compared with crime scene evidence.

But, for a case like the one of the abandoned Bowness child where police have no leads, it likely would leave the case as cold as it was before they brought in Parabon.