Dallas County prosecutors secured a murder conviction on Tuesday in a cold case dating back to 1986 thanks to a promising new forensic technique.

The investigation into 37-year-old Barbara Fay Villarreal’s death at her home in the 3600 block of Colbath Street on November 7, 1986, in Garland had reached a dead end after DNA collected at the scene discounted her husband as a suspect, as previously reported in The Dallas Express.

However, progress in the case stopped until last year, when the DNA was tested using a new forensic genealogy technique.

Liborio Canales, the 86-year-old brother-in-law of a woman slain in her home, pleaded guilty to her murder and was sentenced to 20 years in prison on March 12. He allegedly told investigators that he stabbed 37-year-old Barbara Villarreal to death during an argument over family matters.

This is reportedly the first murder conviction secured using investigative genetic genealogy, per CBS News Texas.

Forensic genealogy employs new DNA technology to scour public databases for “cousin matches,” or relatives of all kinds, as Cheryl Hester, director of forensic and genetic genealogy at Advanced DNA, told CBS News Texas. These databases include information from the users of popular ancestry sites, such as GEDmatch and FamilyTreeDNA, who have opted to share their results.

As previously covered by The Dallas Express, this technique has already solved a few cold cases of other types in North Texas. Earlier this month, 51-year-old Jeffery Lemor Wheat pleaded guilty to raping four women in Plano, Corinth, Coppell, and Arlington during home break-ins between 2003 and 2011, thanks to Plano police deploying genetic genealogy to identify him.

In the case of Villarreal’s murderer, Garland detectives learned that he was closely related to her husband. This helped identify Canales as a suspect, ultimately leading to his arrest by local authorities in Lovington, New Mexico, where Canales had been living.

The murder rate in Garland is below the national average of 6.1 homicides per 100,000 residents, logging just 2.1 per 100,000 residents. In contrast, Dallas’ murder rate is double the national average, clocking a rate of 12.2 homicides per 100,000 residents. As data from the City of Dallas reveals, the overwhelming majority of murder victims are black and Hispanic males.

Hindering its ability to respond to crime is the Dallas Police Department being chronically understaffed. It fields only around 3,000 officers, while a City analysis of public safety requirements by population size recommended a force of 4,000.

Additionally, the Dallas City Council budgeted DPD only $654 million this fiscal year, significantly less than the spending seen on police in other high-crime jurisdictions, such as Chicago, Los Angeles, and New York City.