MURDERED: Sandra Birchmore

Sandra Birchmore joins the Stoughton Police Explorer Program at 13 years-old.

Sandra and Officer Matthew Farwell begin a sexual relationship.

Sandra’s mother passes away from a stroke and weeks later, her grandmother also dies.

Sandra tells Matthew she is pregnant and that he is the father. Their text messages show escalating conflict.

A friend calls the Stoughton Police Department and tells an officer that Sandra is in a sexual relationship with a Stoughton officer or detective. The officer tells Matthew about it, and he tells the person not to speak about it again.

Sandra texts a friend that Matthew is suddenly acting positively about the situation. That same night, Matthew asks for a key to her apartment and the code to her building’s entrance.

Afternoon

Sandra leaves work early because school is closed for a snowstorm and returns to her Canton apartment. Building surveillance shows her coming and going alone.

Just after 5 p.m.

Surveillance shows Sandra picking up a food delivery.

5:31 p.m.

Surveillance shows Sandra briefly stepping outside to brush snow off her car before going back upstairs. This is the last time she appears on camera.

Around 9 p.m.

Matthew texts Sandra asking if he can “come by for a second.” She replies that she will leave her door open for him. This is the last known message she sends.

9:14 p.m.

A tall man, later confirmed to be Matthew Farwell, is seen on surveillance entering Sandra’s building.

9:40 p.m.

Data from Sandra’s iPhone health app records her last movements, suggesting she dies around this time.

9:43 p.m.

Matthew is seen on surveillance exiting Sandra’s building.

Police conduct a welfare check at Sandra’s apartment after she had not shown up to work for days. Sandra is found deceased on the floor by her bedroom closet and Massachusetts State Police label the case a suicide.

Massachusetts State Police interview Matthew Farwell and he admits being at Sandra’s apartment the night she died, but claims he only went to end the relationship. He also claims that when he left, Sandra was alive in the kitchen.

Stoughton Police Chief Donna McNamara places Matthew Farwell on leave while an internal affairs investigation examines potential policy violations.

Chief McNamara holds a public press conference outlining the internal investigation’s findings. She states that Matthew Farwell, his twin brother William Farwell, and former Deputy Chief Robert Devine violated their oaths of office and should be entered into the National Decertification Index. She turns the findings over to the Norfolk County District Attorney.

Sandra’s family files a wrongful-death lawsuit in Norfolk County Superior Court. The suit accuses Matthew, William, and Robert of grooming and sexually abusing Sandra from a young age and implicates them in her death, alleging wrongful death, negligent supervision, negligent retention, pain and suffering, and emotional distress.

FBI Special Agent Chenee Castruita files an affidavit outlining a homicide theory, citing Matthew’s grooming of Sandra, his motive to silence her; her health data and expert testimony that her injuries align with homicidal asphyxia, not suicide.

Matthew is arrested on a federal charge of killing a witness or victim, a count that carries potential death-penalty exposure. He pleads not guilty and is held without bail in a Rhode Island detention facility.

A judgment date in Sandra’s family’s wrongful-death suit is scheduled in Norfolk County Superior Court.