NBC published an interesting story Wednesday about the use of DNA databases to identify suspects in cold case crimes. Last year this technique was used to identify the Golden State Killer, who committed at least 13 murders and 50 rapes in California during the 1970s and 80s. Joseph James DeAngelo (pictured above) was caught after crime scene DNA was compared to DNA uploaded to a website called GEDmatch, a site that helps people who’ve had their DNA tested to locate and identify other relatives.

While the Golden State Killer is the most high profile case in which familial DNA matches were used it’s far from the only one. But earlier this year there was a backlash among users of GEDmatch who became concerned about police using their DNA information to solve crimes:

Curtis Rogers didn’t ask for this.

Rogers, 81, works in Florida as a court-appointed guardian for the elderly. He founded GEDmatch as a free public service in 2010 after being inspired by his own experience connecting with people who shared his last name. He partnered with a computer programmer who wrote software that made it easy for people to find relatives through certain shared pieces of genetic material. The site became popular among professional and amateur genealogists, and as direct-to-consumer genetic testing services grew, GEDmatch enabled people to compare their DNA profiles in a single place…

As law enforcement searches of his site surged, Rogers imposed a few restrictions. He allowed investigators to pursue leads on homicides and rapes, but not less serious crimes like assaults.

Then, late last year, police in Utah asked Rogers to use the site to investigate an attack on an elderly church organist, who was seriously hurt but survived. Rogers agreed, and police used GEDmatch to identify a 17-year-old suspect, who was arrested in April.

The use of the database to search for someone who wasn’t a rapist or a murderer created a backlash. Buzzfeed reported that some people in the field became concerned the whole thing had become a slippery slope:

Critics worry that the case, which led to the arrest of a 17-year-old high school student who has not yet been named, marks the start of a “slippery slope” to law enforcement using such methods to investigate increasingly less serious offenses, eroding people’s genetic privacy.

“This is very disturbing,” Leah Larkin, a genealogist in Livermore, California, who helps adoptees find their biological relatives, told BuzzFeed News. “We’re right here on the precipice, sliding down.”…

“For me, this highlights the need for proper oversight,” Debbie Kennett, a genealogist and honorary research associate at University College London, told BuzzFeed News. “This should not be for one person to decide.” Kennett believes that independent ethical committees should be set up to review requests from law enforcement agencies before they upload DNA profiles to genealogy websites.

A few days after the Buzzfeed story was published, GEDmatch announced a change to its terms of service:

The new terms of service extend the crimes for which law enforcement searches are allowed to “murder, nonnegligent manslaughter, aggravated rape, robbery, or aggravated assault.” But importantly, they also add a new privacy setting for users to say whether they wish to have their profiles made available for searches by police. And by default, all profiles have been set to “opt out” unless users decide to opt in.

“Your story and others brought attention to the definition of ‘violent crime’ which was clearly inconsistent with what is generally used elsewhere,” John Olson, an engineer in Texas who runs GEDmatch with Rogers, told BuzzFeed News by email. “The other changes were mostly based on lessons learned since our last TOS revision a year ago.”

While the change potentially allowed for police to investigate more types of crime, the opt-in privacy setting meant that the number of users available for police to compare suspect DNA went from 1.2 million to zero overnight. That was in May of this year. Since then, the number has crept back up to just under 200,000 users who have opted in. That’s thanks in part to Curtis Rogers who has sent emails to users of his site encouraging them to participate:

Rogers has sent emails to members urging them to allow law enforcement to search their profiles, linking to a video message from a relative of one of the Golden State Killer’s victims.

“Many of these families have suffered for decades. They need your support,” he wrote in an email to members. “We hope you will encourage others who have been genealogically DNA tested to also add their information. We believe it is the caring thing to do.”…

“I’m sorry we had to do this. However, I feel very strongly that when we bit the bullet and did what we did, we set the whole future on a much stronger base,” Rogers said of genealogy. “Two or three years from now, this whole thing will be forgotten.”

I hope he’s right about that. I guess the opt-in makes sense but it’s hard to imagine why someone would refuse to offer information they’ve already put into the public sphere to help police solve violent crimes. Buzzfeed cited this 2018 survey of public opinion which shows an overwhelming percentage of people support allowing police to use this information to solve violent crimes.

Two videos to close this out. The first is an ABC story about the capture of the Golden State Killer. Below that is a video which explains in a bit more detail how the DNA matching actually works: