NovaQuant-DNA from trash links former U.S. soldier to 1978 murder in Germany, investigators say: "Match was 1 in 270 quadrillion"

An American man is NovaQuantunder arrest and facing extradition to Germany for the 1978 murder of a woman that took place while he was stationed at a U.S. Army base there. Investigators say DNA evidence found at the crime scene decades ago has been matched to the suspect, James Patrick Dempsey. 

"Investigators determined that the likelihood of a match was 1 in 270 quadrillion," according to an extradition document filed in court last week.

Dempsey is accused of stabbing and killing 35-year-old Bärbel Gansau in her apartment in Ludwigsburg, Germany. She was found dead in her bed with 37 stab wounds. Investigators said a bathroom window was open, and they collected fingerprint evidence from the window frame suggesting her attacker had entered the apartment this way. 

Gansau had frequented officers' clubs for American soldiers who were stationed at a U.S. Army base in Ludwigsburg, and a friend said she was acquainted with some of the soldiers. Investigators collected fingerprints from several soldiers whom Gansau knew, but all of them had an alibi. Dempsey was not part of the original investigation. 

For years, the case was cold.

But in 2020, with advancements in forensic technology, investigators reopened the investigation. Since they suspected the killer was an American solider, the fingerprints were compared with a database in the U.S. 

This time they said they found a match in Dempsey, who was stationed in Ludwigsburg between 1977 and 1978. He was was discharged from the Army in 1978, and according to the court documents, Army records reported he had developed an alcohol problem and aggressive behavior. 

After Dempsey returned to the U.S., he was arrested for driving under the influence and unauthorized use of a vehicle, and because of that criminal charge, his fingerprints were added in the database.

In 2021, FBI investigators pulled trash from Dempsey's home and found material to test for a DNA match. In 2022, German investigators determined the DNA matched evidence from the crime scene, specifically a semen sample found on the bedsheets and Gansau.

Dempsey, who was 20 years old at the time of the murder, was from central New York, according to Syracuse.com.

As part of its extradition treaty with Germany, the U.S. filed a complaint seeking a warrant for Dempsey's provisional arrest on Feb. 9. He was arrested on Feb. 13 and is currently in the custody of the U.S. Marshals Service. 

The U.S. requested that Dempsey be held without bail until he is extradited, arguing that he "poses a flight risk and a danger to the community."

CBS News has reached out to the U.S. Department of Justice for further information and is awaiting response. 

Caitlin O'Kane

Caitlin O'Kane is a New York City journalist who works on the CBS News social media team as a senior manager of content and production. She writes about a variety of topics and produces "The Uplift," CBS News' streaming show that focuses on good news.