Las Vegas police using DNA, genealogy to solve cold cases

A complicated and sometimes controversial law enforcement investigative technique led to the arrest of a suspected serial killer in California. Now, Las Vegas police are using genetic genealogy to investigate their own cold cases.

Genetic genealogy is the wave of the future when it comes to solving violent crimes, according to Kim Murga, the director of forensic lab services for the Metropolitan Police Department. While traditional DNA testing uses evidence from a crime scene to identify a suspect listed in law enforcement DNA databases, genetic genealogy takes profiles of unidentified people and searches for their distant relatives in public databases.

When you take a DNA profile from a private company and put it into a larger database searching for extended family, law enforcement may be able to see your profile and connect it to a suspected killer or serial rapist, Murga said during an interview with the Review-Journal in November.

“It will link you into relatives that you have to then kind of cull through,” Murga said.

The two biggest databases that law enforcement has access to are familytree.com and GEDmatch, which Murga described as the “brain child” of investigators searching for the Golden State Killer. In April 2018, law enforcement in California arrested Joseph DeAngelo after tracking him down through the database.

DeAngelo is suspected of at least 12 homicides and 45 rapes in California in the ’70s and ‘80s. The Golden State Killer case, while not the first to use genetic genealogy, flung the investigative method into the public’s eye.

When investigators were searching for the Golden State Killer, law enforcement was able to search everyone on GEDmatch, but now users have to “opt-in.”

“That has drastically reduced the amount of profiles that are available,” Murga said, adding that there are about 50,000 profiles on GEDmatch available for law enforcement out of about 1.4 million profiles in total.

‘DNA dead end’

This year, Metro started looking toward the technique to solve cold cases. Because it’s an expensive technique — estimated to cost $5,000 to $20,000 per case, Murga said — Metro uses federal grants and must obey Department of Justice policies.

For a case to be investigated, a large amount of quality DNA must be available, all other investigative techniques and traditional DNA testing have led to dead ends, and prosecutors must agree to take on the case if a lead is found.

Murga described these cases as having experienced a “DNA dead end,” with genetic genealogy testing often the last resort.

Kelley Gauthier, the manager of the biology and DNA detail at Metro’s lab, and Murga declined to name all of the cases Metro has submitted for genetic genealogy testing. But one case has been made public: the 20-year disappearance of 7-year-old Karla Rodriguez.

“This case had been worked so much,” Gauthier said. “There is no (Combined DNA Index System) profile on this case besides the parents; there’s no forensic evidence.”

Karla disappeared near her central valley Las Vegas home on Oct. 20, 1999. No one has been arrested or identified as a suspect.

The case is unique when it comes to genetic genealogy: Police aren’t searching for a suspect. Rather, investigators are hoping that, if Karla is still alive, she or any of her potential children will put their DNA profile into a database. And she could be located if her remains are found elsewhere in the country, and that agency can’t identify her.

In October, Karla’s parents submitted saliva samples for the DNA testing, Murga said. Their DNA already had been entered into the FBI-run Combined DNA Index System. But there were no leads.

“You have to think long term,” Gauthier said. “What if she has a child eventually and that child ends up in the database? Maybe not now, but 10 years from now we may be able to solve this case.”

Privacy concerns

With the advancement of genetic genealogy came privacy concerns from the public and private companies such as Ancestry.com and 23andMe, which have promised to keep users’ information secret.

When law enforcement officials search databases, they aren’t seeing the DNA “raw data,” Murga said. Rather, investigators are seeing that the database has identified a person as a relative of the unidentified suspect.

Once a match is made, investigators may contact those family members while working backward to eliminate family lines. When a potential suspect is identified, federal requirements say investigators should obtain a DNA sample from that person and test it against evidence collected from a crime scene.

Wesley Juhl, a spokesman for the American Civil Liberties Union of Nevada, said concerns over the law enforcement access to DNA information are about protecting people from unlawful search and seizures.

The Department of Justice released an interim policy in November, and a permanent policy on genetic genealogy is due in 2020, but the policy does not equate to laws that police agencies have to follow.

Juhl said lawmakers need to regulate the practice when there are so few guidelines for law enforcement to follow.

“Even suspects in violent crimes have constitutional rights,” he said. “I certainly have no sympathy for murderers, but at the same time the Constitution applies to them, too.”

In a follow-up statement sent in December, Murga said people who “opt-in” to allow law enforcement access to their DNA information are making a “personal choice.”

“While there are pros and cons to submitting DNA to these databases, ultimately the more folks who ‘opt in’ to assist law enforcement, the greater the ability law enforcement has to solve heinous crimes, some of which are decades old,” she said.

‘Just the beginning’

Genetic genealogy testing isn’t going away. In November, a Florida judge allowed a detective to search all of GEDmatch’s database, not just the profiles of people who agreed to law enforcement scrutiny, according to The New York Times.

Since the breakthrough in the Golden State Killer case, at least 50 other killings and rapes have been solved nationwide by using genetic genealogy, The Associated Press reported in June.

“I think this type of technology is going to change the face of crimes,” Murga said. “This is just the beginning of the technology and our ability to harness it.”

Contact Katelyn Newberg at knewberg@reviewjournal.com or 702-383-0240. Follow @k_newberg on Twitter.