WILLIAMSON COUNTY, Texas (KXAN) — The Williamson County Sheriff’s Office shared a huge break Wednesday by identifying the woman killed in a 40-year-old cold case, commonly known as “Orange Socks.”

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Sheriff Robert Chody announced that the victim’s name is Debra Jackson, 23, of Abilene. Authorities found her body wearing only orange socks in a Georgetown-area concrete ditch on Halloween in 1979.

“We know anything’s possible,” Chody said. “We don’t care how long it’s been because after 40 years we’re identifying a victim.”

According to the sheriff, Jackson left her family’s home in 1977 and never returned. Her family did not report her as missing at the time since she had disappeared in the past. Investigators said the family did try to look for her over time.

“They thought she went on her way,” Sgt. John Pokorny said, “never thought anything bad would happen to her.”

Less than two months ago, the sheriff tweeted out a new sketch of “Orange Socks” drawn by forensic artist Natalie Murry, who’s a member of the cold case unit. Deputies hoped to re-ignite conversation and find someone who might have information on the victim.

Chody said Wednesday that a woman contacted his office after seeing that updated sketch.

“The relative said she saw the new forensic image of ‘Orange Socks’ on the news and believed ‘Orange Socks’ may be her missing sister, identified as Debra Jackson,” Chody said.

Investigators from the cold case unit took DNA samples from several relatives and processed those with the help of the DNA Doe Project, which is based in California. That helped finally confirm the name that eluded law enforcement all this time.

Sgt. Pokorny said he recently spoke with some of Jackson’s family members, who became “very emotional” after receiving the news.

“They’re excited and sad at the same time,” Sgt. Pokorny said, “but it’s bringing something to them, to help them move forward.”

Notorious serial killer Henry Lee Lucas confessed to killing the woman and was convicted for it in 1984, but he later took back his confession before dying in prison in 2001.

In-depth: The Henry Lee Lucas Confession — true or false?

Jackson’s death has been ruled as a homicide by strangulation. It remains unknown who killed her, though Chody confirmed Wednesday that that portion of the investigation is still open.

“We haven’t solved the case,” he said, “but we have solved something that’s taken 40 years.”

The Sheriff’s Office is now asking for the public’s assistance in finding out more information about Jackson. Deputies are particularly interested in talking to witnesses who knew Jackson’s whereabouts between the time she left her family’s home in Abilene in 1977 and her death in 1979.

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Investigators narrowed the woman’s timeline and locations over these years to roughly:

• 1977 — Jackson was reportedly working somewhere, but it’s not yet known where.
• 1978 — Jackson worked at a Ramada Inn — now called Camelot Inn — in Amarillo.
• 1978 — Jackson worked at an assisted living facility in Azle, Texas

Anyone who may have worked or come into contact with Jackson during that time is asked to call the Williamson County Sheriff’s Office cold case tip line at (512) 943-5204. You can also visit WCSO’s Cold Cases Facebook page here.

The Williamson County Sheriff’s Office started its cold case unit two years ago. It now includes 17 members, who are mostly retired law enforcement officers. They’re actively looking into 14 unsolved murders.

Timeline to identification

Through the investigation, examiners used visual comparisons between “Orange Socks” and Debra Jackson, which included scars on her lower legs. Those were described as healed, infected insect bites — which the family says are consistent with childhood identification. Additionally, both the body and Jackson had abnormally long toes and oddly shaped earlobes, according to the sheriff.

The process of identification really sped up about a year ago. In August 2018, Chody said investigators sent fingernail clippings taken as evidence during the autopsy for forensic testing.

The results, however, were not strong enough to generate a DNA profile.

In September 2018, additional fingernail clipping DNA material was tested, followed by October 2018 results indicating material from a male suspect. However, no profile could be generated.

In November 2018, investigators contacted the University of North Texas about additional testing for the DNA that it had on file for the case.

Then, in February 2019, investigators sent pubic hair samples for testing.

In April 2019, a March DNA extract was tested. In June, DNA profiles were loaded into GEDMatch, an online genealogy database.

That same month, new forensic sketches were released, and cold case detectives received a call from a potential relative saying she saw the sketches on the news and believed the woman in the sketches could be her long-lost sister.

In July 2019, cold case detectives met with the woman, who informed them that Jackson was last seen around 1977 when she left their family home. A look into Jackson’s Social Security information backed up the possibility, as there was no active Social Security information on Jackson after 1979.

In August, DNA samples from two potential family members were sent for testing and matched profiles for Debra Jackson, conclusively identifying “Orange Socks” as Debra Jackson.

The sheriff said more than 1,000 hours were put into the investigation over 40 years. He warned that justice has no expiration date for anyone who commits a crime in Williamson County.