Ex-police officer’s DNA found on strap used in Sandra Birchmore killing, prosecutors say
The 23-year-old was found dead in her Canton apartment in 2021. New federal filings now link Matthew Farwell to the strap used in her death
Sandra Birchmore, 23, was found on the floor of her Canton apartment in early 2021 with a duffel bag strap around her neck, tied to a closet doorknob.
New federal court filings say DNA from former Stoughton police officer Matthew Farwell was found on that strap.
Prosecutors allege Farwell killed Birchmore and staged the scene to appear as a suicide.
DNA evidence now central to the case
The strap was tested in 2021 by the Massachusetts State Police Crime Laboratory, which identified male DNA but did not compare it to Farwell at the time.
After his arrest in 2024, the FBI obtained a DNA sample from Farwell. Prosecutors say it matches the DNA found on the strap.
“The presence of Farwell’s DNA on the murder weapon… is, of course, highly inculpatory,” prosecutors wrote in the filing.
Case back in focus after new filing
The new details were released in a memo filed by prosecutors opposing Farwell’s request to be released on bail ahead of his trial.
Birchmore’s death was ruled a suicide in 2021. Norfolk District Attorney Michael Morrissey declined to bring charges at the time.
Farwell was indicted in August 2024 following a federal investigation.
He has pleaded not guilty and maintains Birchmore died by suicide.
Additional forensic findings
Prosecutors say Farwell’s sperm cells were found on Birchmore’s underwear. They argue this contradicts his prior statements about when they last had sex and shows what they describe as consciousness of guilt.
His DNA was not found under her fingernails, according to the filing.
Pregnancy and disputed paternity
Birchmore was pregnant when she died.
DNA evidence has excluded Farwell as the father, prosecutors said. They argue he believed he was the father at the time.
Text messages cited in the filing are said to support that belief.
The identity of the child’s father has not been publicly confirmed.
Relationship timeline outlined by prosecutors
Prosecutors allege Farwell began a sexual relationship with Birchmore in 2013, when she was 15 and he was 27, and continued it for years.
They say evidence shows he had other relationships with adult women during that time while maintaining a secret relationship with Birchmore.
Final weeks before her death
A witness told investigators Farwell appeared stressed in the weeks before Birchmore’s death and said he was dealing with a relationship issue.
“When this witness asked if they could help, Farwell said ‘the problem was going to take care of itself,’” prosecutors wrote.
What happens next
Farwell is being held without bail in Rhode Island. He has requested release on $50,000 bail with conditions.
Prosecutors oppose that request. A trial is expected later this year.
