Detective 'Murdered Pregnant Mistress and Tried to Make It Look Like Suicide to Stop Her From Revealing He Raped Her When She was 15'

A Massachusetts grand jury has indicted a former police officer for allegedly murdering his pregnant mistress to keep her mouth shut.

RadarOnline.com can reveal authorities believe Matthew Farwell, then an officer with the Stoughton Police Department, killed his mistress, Sandra Birchmore, to stop her from revealing that they had been having sex since she was just 15.

Levy said Birchmore had survived "years of grooming, statutory rape and then sexual violence all at the hands of Matthew Farwell."

Birchmore, 23, had reportedly been telling friends about her abusive yearslong affair with Farwell, 38.

Another source reportedly tried to inform the Stoughton police of Farwell’s transgressions when Birchmore was underage.

Levy said: "When it became clear to Mr. Farwell that he could no longer control Sandra Birchmore, he allegedly silenced her permanently."

According to the indictment, Birchmore began attending the Stoughton Police Explorers, a program for young people interested in a career in law enforcement, when she was 12.

Farwell, an instructor for the program, became friendly with her, but their relationship turned illicit when she was 15.

Prosecutors claimed Farwell would leave his duties to engage in sex with then-minor Birchmore. Their alleged relationship then continued into her adult years.

The indictment stated: "Building off the years of grooming, Farwell later cultivated a controlling and sometimes abusive relationship with Birchmore. He tracked her location with his cell phone and, as voluminous text messages demonstrate, he engaged in sexual violence."

Feds claimed the violence included the disgraced officer's fantasies of minors and sexual assault. A text message from 2020 from Farwell to Birchmore described one of his wishes.

The message read: “Will you say Matt stop I’m 13 I’m not ready for this omfg please stop.”

Toward the end of the same year, Birchmore and Farwell agreed to have a child together. He agreed to impregnate her "in exchange for her silence about his criminal conduct".

The citation continued: "He became physically violent with Birchmore. She told multiple friends that Farwell had pushed and shoved her, grabbed objects from her hands, and put her in a chokehold."

On January 24, Farwell allegedly began making plans to end Birchmore's life before he chose to make his move a few days later.

Prosecutors wrote: “On February 1, 2021, Farwell decided to act. For him, that day provided at least two advantages: a blizzard was approaching greater Boston, ensuring that no one would notice Birchmore’s absence from work for several days; and Farwell’s wife was hours away from delivering their third child.”

Before he allegedly strangled her, he was accused of "stag[ing] her apartment" to make it look like Birchmore had taken her own life.

Her body was found on February 4 during a wellness check.

In the following days, Farwell reportedly lied to police and tried to delete incriminating text messages and Google searches.

Stoughton police launched an internal investigation into Farwell following the murder and put him on leave; he resigned in 2022.

Stoughton Police Chief Donna McNamara said: “The allegations against the suspect, a former Stoughton Police Officer, represent the single worst act of not just professional misconduct but indeed human indecency that I have observed in a nearly three-decade career in law enforcement,”

Federal investigators arrested Farwell on August 28. He faces life in prison if convicted.

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