Disgraced ex-cop killed Sandra Birchmore to ‘clean up his mess’ after years of abuse, affair: feds

BOSTON — Disgraced ex-cop Matthew Farwell killed pregnant Sandra Birchmore to “clean up his mess” because he knew his years of abusing her as a teen were about to be “exposed,” prosecutors charged Friday in closing arguments.

“He went to clean up the mess he had created years earlier,” Boston federal prosecutor Brian Fogerty told jurors of the married former Stoughton detective. “Clean up the mess by taking Sandra’s life.”

Farwell, 41, who appeared in court wearing a black suit and white shirt, is accused of murdering the pregnant 23-year-old in her Canton apartment and staging it as a suicide to keep her from telling his wife about their years-long affair that started with him sexually abusing her at 15, Fogerty claimed.

The alleged murder was the day before Farwell’s wife had their third child.

Farwell allegedly met Birchmore, a troubled child and aspiring cop, when she was 12 and in the Stoughton Police “Explorers” youth program which he helped run.

It was then, he started grooming Birchmore and created an “out of class connection” to lay the ground work for when he eventually started having sex with her, the prosecutor claimed.

“According to the defendant, this was the best day of his life. Sexually abusing a 15-year-old girl was this man’s single best day,” Fogerty said.

But Farwell’s defense attorney, Kimberly Stevens, maintained Birchmore hanged herself after Farwell went to her apartment to break off their relationship.

Stevens said Birchmore had delusions Farwell would leave his wife and kids and start a life with her, even though Farwell’s twin, William “Billy” Farwell, told her it would never happen.

Billy also slept with Birchmore, as an adult, while he was on duty as a Stoughton cop. He testified at trial with the promise of immunity.

“Ms. Birchmore built a fantasy world around the idea — and you heard it from Billy Farwell — that she would be married to Matthew and have his kids,” Stevens said. “Billy said, ‘That’s not a good idea, that’s never going to happen.'”

Birchmore allegedly told Matthew if he didn’t impregnate her she would reveal their relationship. She became pregnant in December 2020 with a boy — whom Birchmore and Matthew both believed he fathered. But DNA testing later revealed Matthew wasn’t the father.

Matthew has pleaded not guilty to one count of killing a witness and one count of killing an unborn child. If he’s convicted, he could face life in prison.

Jurors began deliberating Friday afternoon.

Billy and Matthew both resigned amid an internal investigation into their relationships with Birchmore.