BOSTON (WHDH) - Federal prosecutors want jurors in the Matthew Farwell murder trial to hear from three women who allegedly had extramarital affairs with the former Stoughton police officer, according to new paperwork filed Monday.
Prosecutors say they have video evidence that Farwell wore a mask when he went to Birchmore’s apartment the night she died.
“Farwell’s attempt not to be seen when he went to Ms. Birchmore’s apartment proves that he was there to kill Ms. Birchmore, and not merely present as a cheating spouse afraid that his wife may find out,” the motion stated.
The defense suggests that the mask was to prevent Farwell’s wife from finding out. But their opening statement Friday made the special relevance of the extramarital affairs clear, telling the jury, “Matthew Farwell is a man who had an affair.”
Prosecutors are now asking that jurors hear from those three women, who they say will testify that Farwell did not take similar precautions to hide their relationships. The motion reads in part, “The evidence will prove Farwell never cared about his wife discovering his infidelity, so he wore a mask on Feb. 1 for another reason: not to be seen at the apartment where Ms. Birchmore lay dead.”
The prosecution said the three women are all prepared to testify. The motion states, “The three affair partner witnesses will say Farwell never took steps to hide their encounters. He never wore a mask or disguise. In fact, he had a cavalier attitude about their encounters.”
Farwell is accused of killing 23-year-old Sandra Birchmore and her unborn child at her Canton apartment in February, 2021. The Massachusetts Medical Examiner initially ruled her death as a suicide, but in announcing their indictment in 2024, federal prosecutors said “Farwell…killed Sandra Birchmore by strangulation…” adding, “…Farwell staged her body and apartment to make it appear as if Birchmore had committed suicide…”
Investigators said Farwell groomed Birchmore for sex, starting when she was 15-years-old and was part of the Stoughton police mentoring program. The United States Attorney’s Office says Farwell murdered Birchmore and her unborn child to keep her from talking about his exploitation of her while he was on duty.
Farwell has pleaded not guilty, and his defense team maintains Birchmore did take her own life.
Testimony is expected to begin Tuesday.
The prosecution’s witness list contains 67 names, including Stoughton Police Chief Donna McNamara. The defense has submitted 97 names of people they may call to the stand.
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