Ethical, legal questions raised surrounding ‘DNA dragnet’ technique in Marrisa Shen case

You’ve likely heard of genetic genealogy testing, and its potential implications for criminal investigations, through the cold case of the so-called Golden State Killer—in which California’s infamous alleged serial killer, rapist, and burglar Joseph James DeAngelo was nabbed after decades at large through DNA testing.

Now, it appears similar technology has been used by homicide investigators in the Lower Mainland, in their quest to locate the person who murdered Marrisa Shen, 13, in Burnaby’s Central Park in July 2017.

But the method in which the DNA of potentially hundreds of men of Middle Eastern descent was gathered, which involved obtaining consent from the men involved, has sparked debate over the ethical and moral boundaries of investigations.

“They did push a lot. They gave me a feeling that, if I don’t do it, it means I’m hiding something,” Zanyar Farhadi, a local realtor who was asked to volunteer DNA, told Global News of the investigators he dealt with.

WATCH: (Aired Nov. 14) Questions about Marrisa Shen murder investigation

2:08 Questions about Marrisa Shen murder investigation

“It was very scary, because the police came to you—and, it’s not like they said, ‘You ran a red light,’ or, ‘You were speeding.’ They said, ‘Your name came out in a murder investigation.’”

Farhadi joins potentially hundreds of members of Metro Vancouver’s Kurdish community who were asked by investigators to volunteer DNA between March and September of 2018—when first-degree murder charges were laid against the case’s prime suspect, Ibrahim Ali.

The Integrated Homicide Investigation Team (IHIT) confirmed at the time that forensic DNA was used in part of their investigative process to locate Ali.

READ MORE: Protest marks court appearance for alleged killer of Marrisa Shen

“With respect to DNA, and the gathering of DNA, that’s the privacy interest in your own body. And there are real protections on that,” explained Vancouver-based criminal lawyer Michael Shapray.

“The problem is, that people—whether they’re educated, whether they’re from this country originally, or if they’ve moved to this country as an immigrant, whether English is their first language, or whether they have legal training—they may not realize that when the police ask them to do something, that they have the right to simply refuse to do it, or not get involved.”

Forensic experts say the technique of casting a DNA dragnet is legal, but it could raise ethical questions as it becomes more commonly used.

“It’s become a more and more useful tool for law enforcement to use. The question is, is that ethical?” Explained Steen Hartsen, a professor at BCIT’s Forensic DNA Laboratory.

“It’s definitely something people should be asking—whether it’s appropriate or not. And there are pros and cons to both sides.”​