A Former Detective is Accused of Sexual Exploitation, Strangling, and Staging a Murder as a Suicide
These Are Just a Few of the Disturbing Allegations in Sandra Birchmore's Death
I'm thinking of Sandra Birchmore's family and friends today. I imagine peace for them was shattered on February 4, 2021, the day when the twenty-three-year-old was found dead in her apartment. She was sitting on the floor in a reclined position with a duffle bag strap tied around her neck and connected to her closet doorknob. Her phone lay just inches from her body. She had been dead for three days and was three months pregnant. By early May, the investigation was complete; the manner of death ruled a suicide.
twenty-three year old Sandra Birchmore
Fortunately, in January 2021, a friend of Birchmore had contacted the Stoughton Police Department to report Detective Mathew Farwell's ongoing sexual exploitation of Sandra. On August 28, 2024, this thirty-eight-year-old now-ex-police detective, husband, and father, Matthew Farwell, was federally indicted in Sandra's death, accused of strangling her and then staging her murder as a suicide. It took three and a half years, an internal affairs investigation, a civil suit, and federal assistance, but justice may be finally coming.
Early Interactions and Grooming Behaviors
Birchmore first encountered Farwell in March of 2010 when she was approximately twelve years old and joined the Stoughton Police Explorers program, where Farwell served as first a police volunteer and then an instructor. The power imbalance and age disparity between a teenage Explorer program participant and an adult instructor created an environment ripe for manipulation.
According to the affidavit, Farwell used his position of authority to groom Birchmore over time. In 2012, he began communicating with her online and friended her on Facebook. He also met her at the Stoughton Public Library, where he continued to sexually groom her under the guise of academic tutoring.
Matthew Farwell
Three years after they met, he took her virginity. She was fifteen, and he was twenty-seven. According to the Motion for Detention, he sent her numerous sexual texts, discussing with her what it was like to be her "first," and stated he wished he could have had sex with her when she was even younger (than 15).
He also discussed violent sexual fantasies, including his desire to pretend to "rape" her. Here is one disturbing excerpt:
"On at least 20 occasions in just the year before her death, Farwell sent Birchmore text messages stating that he would grab her throat, pin her down by her throat, squeeze her throat, or choke her during sexual activity."
Ongoing Exploitation and Control
The affidavit details how the sexual relationship continued for years, with Farwell allegedly using various tactics to maintain control over Birchmore:
Sexual violence: Messages indicate Farwell used forceful sex acts as "punishment" for perceived transgressions. The evidence shows that the defendant used violent sex acts to punish Birchmore for getting bad grades, lying to him, or being sexually active with other people.
Surveillance: Farwell reportedly demanded Birchmore share her phone location at all times and admonished her when she didn't.
Isolation: Farwell frequently instructed Sandra to delete text messages and swore her to secrecy about their relationship, cutting her off from seeking help or support.
Coercion and control: At least two other officers have been accused of having sex with Sandra Birchmore, with both of these occurring at the initiation of Mathew Farwell. One of them was Farwell's twin brother.
However, there is evidence that the dynamics in their relationship were starting to shift. After learning (from someone other than Farwell) that his wife was pregnant with their third child, Sandra told Farwell that she wanted her own child and persuaded Farwell to help her get pregnant. In January 2021, there were heated text exchanges about how much of a mutual decision this pregnancy was; Farwell claimed that Sandra gave him an ultimatum and threatened to disclose their relationship history if she didn't get a baby. She calls it a "compromise," a way for the two of them to maintain their relationship and for her to get what she wants.
What becomes clear over the next several weeks is that Mathew Farwell does not want this child. He is furious when Sandra's friend contacts the police department about his relationship with Sandra on January 20, 2021. His interactions with her become increasingly violent. According to the indictment, he strangled Sandra to death on February 1, 2021, the day before Mathew Farwell's wife gave birth to their third child.
It was supposed to look like a suicide. In May 2021, the medical examiner ruled that the manner of death was self-inflicted, with the cause of death being "asphyxia by hanging." Fortunately, internal affairs had already begun an investigation. The FBI also got involved.
Clues to a Staged Suicide
If Farwell did stage Sandra's death to look like a suicide, the verbal staging began on February 6; when questioned by police, he made multiple false statements about his relationship with Sandra. He also planted false seeds of Sandra's "mental problems," telling detectives that she had been hospitalized involuntarily "many times." [Sandra had been briefly hospitalized once after a family dispute and was found not to be at risk for self-harm].
Every seasoned homicide detective will tell you that every unexpected death should be investigated as a homicide until proven otherwise. The 99.9 percent who are honest will also tell you this is rarely possible. So, when faced with what initially appears to be a suicide, here are a few questions that are most likely to help investigators hone in on a crime scene that has been staged:
Is there a viable alternative explanation? Which is more likely: the suicide of a twenty-three-year-old in the early stages of a planned pregnancy with aspirations of being a teacher or the murder of a twenty-three-year-old whose secrets could potentially destroy the career and family of a selfish and controlling abuser? Farwell's wife was getting ready to deliver their third child. Not only would his law enforcement career be over if it came to light that he had used his police authority to take advantage of a trusting teen, he could face criminal charges for statutory rape.
Was the deceased making plans?
Sarah wanted this baby. She had planned this pregnancy with Farwell's initial consent. But she had made it clear to friends and family that, Farwell's involvement or not, she would be mothering this child no matter what. She had an OBGYN appointment scheduled for February 10, 2021.
On the day she died, Sarah Birchmore had been making calls to schedule a newborn photo shoot. She had recently been texting friends about obtaining baby clothes. At 8:25 PM on February 1, just hours before her estimated time of death, Birchmore performed a Google search for "Cubby Kids" furniture.
Sarah had dreams of becoming a teacher and had taken steps toward meeting that career goal.
Was the victim in a violent relationship?
Multiple witnesses reported that Farwell had become physically aggressive with Birchmore in the weeks leading up to her death, particularly when discussing her pregnancy. One friend noted that Birchmore had described Farwell putting her in a headlock and grabbing her phone; another described an incident during which Farwell allegedly pushed Sarah to the ground after she showed him a sonogram. Her therapist also reported That Sarah had talked about being shoved by Farwell.
What do friends and family say? Yes, some families indeed have a hard time accepting a loved one's suicide. No, it's not true that most survivors of suicide loss cling to the belief that their family member has been murdered. When the family of an alleged suicide says their loved one would never commit suicide and has a definite suspect in mind, it's worth taking a second look.
None of Birchmore's friends or family members interviewed believed she was suicidal. Her therapist had a session with Birchmore on January 31, 2021 - the day before her death. During this session, Person 7 screened for depression and suicidal ideation and found no signs of either. Multiple witnesses described Birchmore as excited about her pregnancy and plans.
Are there inconsistencies between the initial hypothesis/explanation and the physical evidence?
When family members entered Birchmore's apartment after her death, they found laundry in progress - wet clothes in the washing machine and dry clothes in the dryer. People who die by suicide do not pause to do so in the middle of routine household chores.
Investigators found Birchmore's necklace nearby, broken with a large clump of hair caught in the chain. This finding raises the possibility of a struggle.
Her phone, typically described as her "third hand" by friends, showed no activity after 9:13 PM on February 1, despite being found near her body.
Dr. William Smock, an expert consulted in the case, noted several inconsistencies with suicide by hanging:
The fracture of Birchmore's hyoid bone, which is uncommon in seated hanging; a pattern imprint on Birchmore's chest consistent with blunt force trauma; and abrasions on Birchmore's nose, which is consistent with suffocation attempts
Are people behaving out of character?
In the week before Sandra's death, Farwell had asked her for a key to her apartment, a change from his previous stance that keeping a key was a bad idea. He also began examining the closets and spaces of her living quarters, behaving unusually enough for Sandra to mention it to a friend.
Sandra commented to more than one friend that Farwell had suddenly become nicer to her a week before she died.
Surveillance footage showed Farwell entering Sandra's building on February 1 at 9:14 PM wearing a face mask, despite witnesses stating he typically resisted wearing face masks during the pandemic.
The Bottom Line
To date, no one has been convicted in Sandra's death. If not for the diligent effort of internal affairs, Sandra's family and friends, and the FBI, it is possible no one would ever have been. The mounds of evidence pointing to homicide after Sandra's death underscores the importance of thorough investigation in cases of suspicious deaths, particularly where there's a history of domestic violence or sexual exploitation.
Investigative bias, an incomplete initial assessment, lack of specialized training, resource constraints, or special courtesy can all contribute to a premature conclusion. For law enforcement, this case highlights the critical need to look beyond surface appearances and consider the full context of a victim's life, relationships, and recent behaviors when investigating a potential suicide.
Thank you for reading this issue of The Mind Detective. Please pass it along to your true-crime-following friends. I hope everyone had a relaxing Labor Day weekend.