Edward Morgan (via Dallas County Jail)

Police in Texas say that forensic DNA technology helped them crack the cold case of a 21-year-old woman who was sexually assaulted and murdered nearly 40 years ago.

Edward Morgan, 60, has been arrested for the 1984 capital murder of Mary Jane Thompson, the Dallas County District Attorney’s Office announced in a press release Thursday.

Thirty-eight years ago, Thompson’s body was found behind a Dallas warehouse. She had been sexually assaulted and murdered on Feb. 13, 1984, police said.

According to a report in the Dallas Morning News, she was an aspiring model working at a florist’s shop and a restaurant. She had lived in Houston and Los Angeles, and had moved to Dallas six months before he death, the Dallas Morning News reported.

She was last seen on Feb. 11, 1984, when she took a bus to the Trinity Medical Clinic, the Dallas Morning News report said.

The victim’s body was discovered two days later near some out-of-use railroad tracks behind a warehouse, according to the Dallas Morning News. She had been strangled with her own leg warmers, the report said.

Her assailant had remained at large since then, according to the press release.

In 2009, Dallas Police reopened the case and conducted DNA testing on swabs taken from Thompson’s autopsy, the press release said.

That testing identified an unknown male DNA profile that was never matched to a specific suspect, and the case went cold again.

Then, in 2018, Dallas Police Cold Case Homicide Detective Noe Camacho reopened the case, the press release said. Camacho worked with a team from the Dallas County DA Sexual Assault Kit Initiative (SAKI) that was using new types of forensic testing techniques.

The FBI joined the task force in 2020, Dallas Police say, and the case was submitted for forensic genetic genealogy analysis. This technology identified Morgan as a suspect, and this week, police said, DNA testing confirmed that Morgan matched the unidentified profile from the swab taken in the 1984 autopsy.

As Dallas Police pointed out, this was the same technology used to catch Joseph James DeAngelo, the serial murderer known as Golden State Killer. Forensic genealogy matches suspects’ DNA to data uploaded on commercial ancestry websites and can be used to find possible relatives to the suspect.

Although the practice has led to the arrests of suspects in decades-old cold cases, forensic genealogy analysis has also raised privacy concerns.

After Morgan was arrested, Thompson’s sister Selena Tomasello posted several messages to Facebook, CBS News reported.

“Missing you sis on Friday when [I] got that call [I] been waiting 38 years for[.] [T]he FBI find him sis he will be in jail for the rest of his life he is know [sic] longer free as a bird [I] know you are looking down,” Tomasello posted. “And happy that they finally got him[.]”

“I got the call [I] been waiting 38 years for,” Tomasello also posted. “[T]he FBI called in to tell me they fond [sic] the guy that killed my sister 38 years ago they arrested him[.] [W]hen [I] got that call [I] was at Roswell cancer hospital waiting in waiting room and my second answered pray is [I’m] cancer free[.] [M]y nephew ray said that my sister was thanking me for never giving up on finding him and for not giving up the fight against cancer the best thank you gift [I] ever got. God is good.”

Capital murder in Texas is punishable by the death penalty.

According to county records, Morgan is currently being held at the Dallas County Jail on $500,000 bond.

[Image via Dallas County Jail.]