LANCASTER COUNTY, Pa. (WHTM)– David Sinopoli, the man who killed 19-year-old Lindy Sue Biechler and ended up eluding authorities for decades in Lancaster County’s oldest cold case, pleaded guilty Thursday.

Sinopoli, 69, was sentenced by Lancaster County President Judge David Ashworth to spend between 25 and 50 years in prison, the District Attorney’s Office said in a news release.

While in Lancaster County court, Sinopli pleaded guilty to charges of third-degree murder, aggravated assault, and burglary after DNA evidence linked him as Biechler’s killer on Dec. 5, 1975.

“David Sinopoli, you took a huge part of my life from me and caused an extraordinary amount of pain and suffering for so many people,” Phil Biechler, Lindy’s former husband said. “While others had to live their life with the terrible consequences of the murder you committed, you got to live your life out. So, I have to ask you, ‘Why did you do this?’ While I forgive you because my God tells me to, you need to pay for your actions.”

Biechler had just gotten back home from grocery shopping in the evening when she was attacked and stabbed multiple times. Her aunt and uncle discovered her body and contacted the police.

Biechler, according to prosecutors, was found lying on her back with a knife sticking out of her neck, and a tea towel was wrapped around the handle. Signs of a struggle were present at the scene.

An autopsy discovered that Biechler was stabbed 19 times in the neck, chest, upper abdomen and back

Advancements in DNA technology were instrumental in helping authorities make an arrest.

In 1997, the Lancaster County District Attorney’s Office submitted evidence from the crime scene for DNA analysis.  As a result, a male DNA profile was obtained from the right-side area of Biechler’s underwear and was determined to contain semen. In 2000, this DNA profile was submitted to CODIS, a nationwide database that contains DNA profiles of individuals convicted of certain crimes.  Investigators never received a hit on this case’s entry into the CODIS system.   

Sinopoli’s Italian ancestry made him a possible person of interest through the DNA evidence left at the scene.

Officials were then able to use DNA from a coffee cup Sinopoli discarded at Philadelphia International Airport in 2022, and that matched the DNA that was found at the scene decades ago.

The match statistic on the DNA left at the scene and the coffee cup was around 10 trillion.

“The defendant thought he had gotten away with this horrific murder while he carried on with his life for 48 years,” Assistant District Attorney Christine Wilson, who prosecuted the case, said. “However, never forgetting about Lindy Sue Biechler, the hard work of many involved in trying to solve this case for years and the advancement in DNA and technology caught up with him. Justice for Lindy has finally occurred.”

“I would like to apologize to everyone, including my wife,” said Sinopoli when given an opportunity to speak in court.

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