Trial begins for former Massachusetts police officer accused of killing pregnant woman he was involved with

EDITOR’S NOTE: This story involves a discussion of suicide that some readers might find upsetting. If you feel you are in crisis, call or text 988 to reach the 24-hour suicide crisis helpline.

Boston —

The trial of a former police officer accused of killing a young woman five years ago in her suburban Boston apartment opened Friday with two very different accounts of Sandra Birchmore’s final days.

Birchmore, 23, was found slumped on her bedroom floor in Canton, Massachusetts, with a duffel bag strap looped around her neck and attached to a closet door handle. Local and state authorities ruled her death a suicide on Feb. 1, 2021, but federal prosecutors took over the case three years later and charged former Stoughton police officer Matthew Farwell with killing her. He pleaded not guilty.

Assistant U.S. Attorney Torey B. Cummings told jurors that Farwell was supposed to be Birchmore’s mentor, but that he first had sex with her when she was 15 and he was 27. Cummings said he exploited her for years – sometimes meeting Birchmore for sex while on duty – and eventually killed her after she became pregnant and he feared their secret relationship would be exposed.

“She could end her life with the information she had, so he decided to end his life first,” Cummings said.

But defense attorney Kimberly Stevens portrayed Birchmore as an anxious, lonely and struggling young woman who had less than $3 in her bank account and who became suicidal after Farwell broke up with her. Stevens admitted that the married Farwell had an affair with Birchmore and made mistakes, but insisted to jurors that he did not kill her.

Instead, Stevens told jurors, Birchmore killed herself in an “act of impulsive desperation” after Farwell broke up with her that night.

Birchmore’s family pressured investigators to reconsider the suicide decision, saying she was planning for her future and was excited to be a mother. A federal investigation led to Farwell’s indictment in 2024, and in April the medical examiner’s office changed the circumstances of Birchmore’s death to “undetermined.”

Farwell, 40, is accused of murdering a witness or victim – essentially to prevent Birchmore from potentially incriminating him. (It is a federal offense to engage in a sexual act with someone under 16 if the other person is at least four years older.) He also faces a second charge — related to Birchmore’s pregnancy — of violating a federal law protecting unborn children.

DNA testing later ruled out Farwell as the father of Birchmore’s unborn baby. But prosecutors said he thought the child belonged to him at the time of his death.

Farwell was decertified as a police officer and barred from working in law enforcement in Massachusetts. He has been in prison since his arrest in August 2024 and if convicted, he faces a potential sentence of life in prison.

His trial, at the John J. Moakley Courthouse in Boston, is expected to last about a month.

Cummings portrayed Birchmore as a vulnerable young woman who grew up idolizing police officers, only to be groomed by the one who used and discarded her.

Farwell, looking stoic, sat between his two lawyers dressed in a charcoal gray suit and looked mostly at a computer screen on the defense table as Cummings presented the prosecution’s case. Occasionally, he glanced to his right toward the jury box, where 16 jurors — including four alternates and six women — sat and watched.

Cummings referred to Farwell as “the defendant,” unlike Stevens, who called him “Matt” during his opening statement and at one point put his arm on his shoulder.

Six of Birchmore’s cousins ​​were in the courtroom Friday for their opening statements, a family member told CNN.

Birchmore’s mother had been facing a series of health problems and Birchmore’s father was not present, Cummings said. So in 2010, Birchmore’s mother enrolled her daughter in the Stoughton Police Department’s Explorers program for area youth, hoping she would get structure and meet positive role models.

The teen had struggled in school, was diagnosed with ADHD and had trouble making friends, Cummings told jurors. The prosecutor showed a group photo of children in the Explorers program and pointed out that at 5 feet, 10 inches, Birchmore was the shortest.

Birchmore was “in love” with police officers and spent many hours at the police department, Cummings said. Farwell was one of the police officers she trusted, and in late 2012, when Birchmore was 15, he sent her a friend request on Facebook and then began tutoring her at a local library, according to the prosecutor. But what started as a mentoring relationship quickly became sexual, Cummings said.

“He gave her the attention she needed,” she said. Cummings described an illicit sexual relationship that lasted about eight years. It relied on secrecy and control and included fantasies of rape and rough sex initiated by Farwell, the prosecutor said.

Authorities discovered some 40,000 messages between Farwell and Birchmore on her electronic devices that offered a digital record of a relationship that began when she was a minor.

“He told her that the day he took her virginity, when she was 15, was the best day of her life,” Cummings told the jury, referring to a text message exchange. “Sandra’s first sexual experience involved a crime,” she added.

Farwell married in May 2013, about a month after he first had sex with Birchmore, Cummings said. After Birchmore learned that Farwell was expecting his third child with his wife in February 2021, she began pressuring him to have a baby with her and threatened to tell his wife, the prosecutor added.

“She was going to report her crime…over the last 10 years,” Cummings said.

The prosecutor said Farwell agreed to his requests to appease him and keep their relationship a secret. But “she kept asking for more, she kept changing the terms of the deal,” Cummings told jurors. “The accused was not happy about it.”

Cummings said that in January 2021, a friend of Birchmore called Stoughton police and told a dispatcher about the illicit relationship, infuriating Farwell.

She also said Birchmore told a few people she planned to publicly share her baby news on Valentine’s Day and had prepared a poster for social media saying, “I’m expecting a new little one to love.”

Cummings told jurors that on the evening of Feb. 1, 2021, Farwell texted Birchmore and asked if he could come over. She told him she would leave the door open. It was the last message coming out on his phone.

Farwell arrived four minutes later, wearing a dark hooded sweatshirt and a medical mask, the affidavit states. The surveillance video, played by Cummings to jurors, showed him entering his apartment building and then leaving about a half-hour later.

Cummings told jurors that Farwell staged her crime to look like a suicide and believed people would accept that conclusion because Birchmore was a vulnerable young woman.

But authorities found his DNA on the bag strap around Birchmore’s neck, she said.

Stevens, the defense attorney, offered a different explanation for Farwell’s visit that night. In her opening statement, she said he went to Birchmore’s apartment to break up with her.

She portrayed Birchmore as an unstable woman who texted Farwell relentlessly, including on the day of his death. Stevens read some texts aloud to jurors:

“I’m sorry, I’m in need today. Can I send you a message tomorrow before the snow arrives?”

“I took my medicine just so you know.”

“I wish you were here with me tonight, sad face.”

“I keep waking up.”

“I couldn’t sleep last night.”

Stevens said the barrage of text messages showed a young woman struggling with anxiety.

“She dreamed of having a relationship that would result in a child and a home that she never had,” she told jurors.

“It’s a window into his mental state. Thanksgiving alone, Christmas alone, no family,” she added. Birchmore couldn’t pay her rent and had expressed fears that she would have spots and that her pregnancy was in danger, Stevens said.

When her body was found, Birchmore was wearing turquoise leggings and a dark down jacket, and neither showed tears or other signs of a struggle, Stevens said. She also said that Farwell’s DNA was not found under Birchmore’s fingernails and that the ligature found around her neck contained the DNA of several people – not just Farwell.

“Proof of commingling is never proof,” Stevens told jurors. “At the end of the testimony, you will find that the government has not met its burden beyond a reasonable doubt. »