A 69-year-old Lancaster man will serve up to 50 years in prison for killing 19-year-old Lindy Sue Biechler nearly 48 years ago in her Manor Township home.

David Sinopoli, of the 300 block of Faulkner Drive, pleaded guilty Thursday in Lancaster County Court to third-degree murder, aggravated assault, and burglary regarding the Dec. 5, 1975, killing of Biechler that went unsolved until investigators used DNA evidence technology to connect Sinopoli to the crime, resulting in his arrest on July 17, 2022.

“Because of the dedication of many law enforcement officers from multiple agencies over the years, justice was finally obtained for Lindy Sue Biechler,” Lancaster County District Attorney Heather Adams said. “The DNA evidence obtained in the case and analyzed by Parabon revealed exactly who Lindy’s killer was and the sentence imposed today by the Court will serve as a much-deserved life sentence for the 69-year-old defendant.”

Lancaster County President Judge David Ashworth accepted the guilty plea and sentenced Sinopoli to 25 to 50 years in prison.

Assistant District Attorney Christine Wilson prosecuted the case, which was the oldest cold case in Lancaster County, and acknowledged a photo of Biechler displayed next to the defendant in the courtroom.

“These cases are never forgotten. Lindy Sue will never be forgotten. While the defendant was able to carry on with his life, Lindy was extinguished by him. Look at her!” Wilson said to the defendant while pointing to the photo. “And the precious life you stole in 1975.”

Sinopoli glanced at the photo without reaction. He stated, “I would like to apologize to everyone, including my wife,” when given the opportunity to speak by Judge Ashworth.

“The enormity of the damage you have caused is incomprehensible,” Judge Ashworth said to the defendant before accepting the plea, ordering sentence, and remanding Sinopoli to Lancaster County Prison to await transportation to the Department of Corrections. “The depravity of your actions cannot be overstated.”

Judge Ashworth also noted the significance of DNA science, the dedication of law enforcement, and the defendant only pleading guilty because he was caught, not because he was remorseful.

Obtaining justice in this case was a decades-long culmination of investigation by multiple agencies, most recently the one conducted by Lancaster County Detectives Chris Erb, Larry Martin, and Wilson, who supervises the Lancaster County District Attorney’s Office Cold Case Unit and also prosecuted the 1992 cold-case murder of Christy Mirack.

“The defendant thought he had gotten away with this horrific murder while he carried on with his life for 48 years,” Wilson 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.”

Three of Lindy’s family members spoke during the proceeding and Wilson read statements from another. Lindy’s family members provided input in the guilty plea and agreed with the sentence.

“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.”

Sinopoli must also pay over $25,000 in court costs for DNA lab expenses.

Biechler, 19, was found dead in her Manor Township apartment on the evening of December 5, 1975; she was stabbed multiple times at her Kloss Drive home after returning from the grocery store in the early evening hours.  Her aunt and uncle discovered her at approximately 8:46 p.m. and called police.

Investigators observed blood on the outside of the front door as well as the wall on the entrance way and several patches of blood on the carpet of Biechler’s home.  Biechler had returned home from the grocery store between 6:45 p.m. and 7:05 p.m. and grocery bags from John Herr’s market sat on the dining room table.  Investigators observed signs of a struggle inside the apartment and observed Biechler lying on her back with a knife sticking out of her neck with a tea towel wrapped around the wooden handle. The knife matched the knives stored in Biechler’s knife block in the kitchen. 

The Lancaster County Coroner’s Office ruled the cause of death as massive bleeding due to multiple stab wounds and the manner of death as homicide.  Biechler had sustained 19 stab wounds to her neck, chest, upper abdomen, and back.

Detectives from Manor Township Police Department, with assistance from the Pennsylvania State Police, conducted an in-depth investigation into the homicide and followed multiple leads over the years clearing dozens of people.  The investigation spanned decades with evidence being sent to multiple laboratories and interviews of multiple subjects being completed. 

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 which contains DNA profiles of individuals convicted of certain crimes.  Investigators never received a hit on this case’s entry into the CODIS system.  

In January 2019, with the agreement of the Manor Township Police Department, the case was taken on by Lancaster County District Attorney’s Cold Case Unit.

In June 2019, the Unit enlisted the help of Parabon NanoLabs to analyze DNA in the case using its Snapshot Advanced DNA analysis service. In September 2019, investigators released composites, also called phenotypes, provided by Parabon based on DNA evidence left at the crime scene.  These composites revealed characteristics of the suspect including skin tone, eye color, and hair color.

In December 2020, the Lancaster County District Attorney’s Office requested that Parabon proceed with further genetic genealogy analysis.  Parabon’s genetic genealogy research ultimately identified Sinopoli through his Italian ancestry as a possible person of interest.

On February 11, 2022, investigators surreptitiously obtained DNA from Sinopoli from a coffee cup he used and threw into a trash can before traveling at the Philadelphia International Airport.

The coffee cup was then submitted to DNA Labs International for testing and in April 2022, it was determined that the DNA on the coffee cup contained a mixture of DNA with one male contributor.  The electronic data files from DNA Labs International were then forwarded to Cybergenetics, a Pittsburgh laboratory that specializes in separating DNA mixtures. Cybergenetics’ computer analysis concluded that the DNA on Sinopoli’s coffee cup and DNA identified in the semen on Biechler’s underwear had a match statistic around 10 trillion.

Detectives then consulted with a blood spatter expert to determine if any blood left behind on Biechler’s clothing would be consistent with having been left behind by the suspect.  The expert identified two blood spots on the exposed part of the victim’s pantyhose which were also sent to DNA Labs.  In June 2022, the blood drops were determined to be consistent with the DNA profile obtained from Biechler’s underwear. 

Our office thanks the Manor Township Police Department, Pennsylvania State Police, CeCe Moore and Parabon NanoLabs, and everyone involved in this case from beginning to end. After nearly 48 years, justice has finally been served for Lindy Sue Biechler.

MEDIA CONTACT: Sean McBryan, semcbryan@co.lancaster.pa.us; Twitter: @SeanMcBryanLanc.