On the evening of December 5, 1975, Lindy Sue Biechler returned to her apartment in the Spring Manor complex in Manor Township, Lancaster County, Pennsylvania. She was 19 years old, newly married, and had just stopped to deposit a paycheck before bringing home groceries.
Between 6:45 and 9:00 p.m., someone attacked her inside her living room. She fought back, but the attacker used two knives, one brought from outside and one taken from her kitchen. She was stabbed 19 times in the neck, chest, abdomen, and back.
When her uncle and aunt stopped by to exchange recipes, they found her on the living room floor. A knife was still embedded in her neck, wrapped in a dish towel to hide fingerprints. A man’s footprint was found in the kitchen, and the autopsy confirmed both severe blood loss and signs of sexual assault.
The timing of the attack was narrow, between when Lindy arrived home and when her husband, Phil Biechler, was expected back. Investigators believed the killer knew her schedule and knew she would be alone.
Police formed a task force, interviewed 300 people, and consulted criminologists from outside agencies. Phil Biechler was questioned and cleared. No suspect emerged. No lead went anywhere.
The only physical evidence from the killer was a DNA sample collected from semen on Lindy’s underwear. In 1975, there was no technology to analyze it, so investigators carefully packaged and stored it. They knew it was the most important item in the case, even though they could not use it.
Decades passed. In the 1990s, DNA testing became part of the American justice system, and the sample was submitted to CODIS, the national DNA database. There were no matches. The killer had no criminal record and no reason to be in any database.
In 2019, the Lancaster County District Attorney’s Office cold case unit asked Parabon NanoLabs to create a composite image of the suspect from the crime scene DNA. Two images were released to the public in September 2019. No significant tips came in.
Then, in 2018, the arrest of the Golden State Killer in California introduced a new technique to the public: genetic genealogy. Instead of searching criminal databases, investigators searched public genealogy databases for relatives of the suspect and built family trees to narrow down the individual.
In 2020, the Lancaster County cold case unit reached out to CeCe Moore, the chief genetic genealogist at Parabon NanoLabs. Moore had helped solve hundreds of cold cases, but this one was different.
The closest DNA matches in the public genealogy database were extremely distant relatives, people who shared common ancestors with the killer from the 17th or 18th century. Moore had to trace the family tree back through centuries, a task she described as the hardest of her career.
After months of work, she identified a common point among the DNA matches. Their ancestors all originated from Gasperina, a small village in Calabria, southern Italy. Moore then traced the family lines forward through migration and settlement to find which family from Gasperina had come to Lancaster County.
The list narrowed to a small group. One of the names was David Sinopoli.
Sinopoli was 68 years old and living in East Hempfield Township, Lancaster County. He had no criminal record and no police file. In 1975, he had lived in the same four-unit building at Spring Manor as Lindy and Phil Biechler, just steps away from the victim.
Investigators did not approach him directly. They needed his DNA but did not have enough evidence for a court order. So they placed him under surveillance and waited for him to discard something.
On February 11, 2022, Sinopoli went to Philadelphia International Airport. He drank coffee and threw the cup in the trash. Investigators retrieved it and sent it to the lab.
The DNA from the coffee cup matched the semen DNA collected from Lindy’s underwear. The match probability was approximately one in 10 trillion. Blood stains on the same clothing confirmed the result.
On July 17, 2022, investigators arrested David Sinopoli at his home in East Hempfield Township. It was 46 years, 7 months, and 12 days after the murder.
District Attorney Heather Adams announced the arrest at a press conference the next day. She said the case was solved thanks to advances in DNA technology and that without it, she did not know if it would ever have been solved.
Sinopoli was held in jail for more than a year. On October 19, 2023, he pleaded guilty to third-degree murder, aggravated assault, and burglary.
In the courtroom, Assistant District Attorney Christine Wilson placed a photo of Lindy Sue Biechler next to the defendant’s seat. She pointed at the photo and told Sinopoli that Lindy would never be forgotten.
Phil Biechler, who had lost his wife at age 20, spoke directly to Sinopoli. He said Sinopoli had taken a huge part of his life and caused immeasurable suffering while being able to live his own life.
When given the chance to speak, Sinopoli said only one sentence: “I want to apologize to everyone, including my wife.” He offered no explanation for the murder, no reason for the 19 stab wounds, and no words about the night of December 5, 1975.
Judge David Ashworth sentenced him to 25 to 50 years in prison, the maximum under Pennsylvania law in 1975. At age 69, that sentence was effectively a life sentence. Sinopoli was also ordered to pay $25,210 in prosecution costs.
The case was the oldest unsolved cold case in Lancaster County history. It was solved only because the DNA sample had been preserved for nearly half a century and because CeCe Moore developed a new method to trace a family tree back four centuries to a small village in southern Italy.
That method has since become a tool for other cold cases that previously seemed impossible to solve through genetic genealogy.
The case also left practical lessons. Lock your doors, even in quiet neighborhoods. Be cautious with people in your own building. Let loved ones know your schedule. Trust your instincts. And remember that DNA never lies and never forgets, even if it takes 47 years for justice to arrive.