Jurors in the federal trial of a former Massachusetts police officer accused of killing a woman he allegedly abused as a teenager were shown disturbing photographs from the crime scene.

Matthew Farwell, 40, is charged with strangling 23-year-old Sandra Birchmore in early 2021 after she told him she was pregnant, then allegedly arranging the scene to make her death appear to be a suicide.

Farwell served with the Stoughton Police Department from 2012 until 2022. Prosecutors say he first encountered Birchmore through the department’s police explorers program when she was 12 years old.

According to the government’s case, Farwell used his position to groom Birchmore before sexually exploiting and abusing her at age 15. Prosecutors also allege that their sexual relationship continued after she became an adult.

Birchmore learned she was pregnant in late 2020 and informed Farwell, according to the federal indictment filed in the U.S. District Court in Massachusetts.

Prosecutors allege that Farwell strangled Birchmore on or around February 1, 2021, and then drew on his law-enforcement experience to arrange her apartment in a way that suggested she had taken her own life.

Farwell has pleaded not guilty. His defense maintains that Birchmore died by suicide after he ended their relationship. Our News Outlet has contacted his attorneys for additional comment.

During the first week of the federal murder trial, jurors saw graphic photographs of Birchmore’s body. She was discovered in her bedroom on February 4, 2021, after an officer was sent to her apartment for a welfare check.

Canton Police Officer Ensley Cotard testified Tuesday that he was dispatched to check on Birchmore after she failed to report for work, NBC Boston reported.

Cotard said Birchmore’s school, where she worked as an instructional assistant, requested the welfare check. When he arrived at her apartment, he obtained a key from the property’s leasing manager.

He testified that he first knocked on the door. After receiving no response, he used the key to enter the apartment.

Cotard told the court that he found Birchmore in her bedroom, positioned near a doorway. A ligature was around her neck and attached to the doorknob, he said.

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The officer testified that he did not see a suicide note. He added, however, that searching for one was not part of his assignment because he had been called to conduct a welfare check.

The prosecution is being heard in federal court after the FBI revisited Birchmore’s death, which had initially been classified as a suicide.

Federal investigators accuse Farwell of killing Birchmore to prevent her from revealing the alleged abuse. The case is therefore being pursued as a federal witness-tampering homicide prosecution.

In opening statements Friday, prosecutors said Farwell killed Birchmore three days before her body was found because she had threatened to tell his wife about their affair. His wife, prosecutors said, was also heavily pregnant with the couple’s third child at the time.

Footage showed Farwell entering Birchmore’s apartment wearing a mask on the night of the murder, but his lawyers claim he went there to break up with her and she killed herself after he left.

It has since been revealed that Farwell’s twin brother, William, also a Stoughton officer, and Deputy Police Chief Robert Devine also had sexual relationships with Birchmore while she was in the Explorers program. 

An internal police investigation concluded that the three officers had ‘inappropriate’ relationships with Birchmore, while an attorney for her family accused them of ‘passing her around like a toy.’

A DNA test done after Farwell’s arrest showed the baby was ultimately not Matthew Farwell’s.

Birchmore’s family has since filed a wrongful death lawsuit against all three men, claiming that she was groomed as a teen in the police explorer program, People reported. 

Devine denies any sexual relationship with Birchmore, while William claims she was a consenting adult when they had sex.