Matthew Farwell's twin William was back on the stand Tuesday at federal court in South Boston and testified that he didn't believe his brother was that "dumb" to have sex with Sandra Birchmore before she turned 16 years old.
Matthew Farwell, a former Stoughton, Massachusetts police officer, is accused of killing the 23-year-old Birchmore and her unborn baby at her apartment in Canton in February 2021. Prosecutors say he staged it to make it look like a suicide to cover up a years-long affair with Birchmore that began when she was just 15.
Farwell is now on trial for killing a witness or victim and causing the death of an unborn child. He has pleaded not guilty to both charges.
His twin brother, William, took the stand late Monday afternoon for about half an hour. He admitted having his own sexual relationship with Birchmore, but he's testifying under the promise of federal immunity because he could be charged with a criminal offense for having sex while on duty as a police officer.
William "Billy" Farwell told the jury his affair with Birchmore began when she was 20 and at the time he did not know she was having sex with his brother. Billy Farwell had his police certification permanently revoked in 2024.
Text messages displayed during testimony on Tuesday shows that Birchmore texted William Farwell in May of 2019 to say that his brother found out about their sexual relationship.
"We got into a massive fight and I was told I have to re-earn trust and everything," Birchmore texted.
William Farwell testified that he never had a conversation with his brother about their respective relationships with Birchmore while she was alive. In the text messages that day, he asked Birchmore when she and his brother first had sex.
"I was 15," Birchmore said.
"Nice," William Farwell replied.
The prosecutor asked Farwell why he responded that way.
"Two reasons," he said. "The first was I didn't necessarily believe her, and the second was I didn't believe my brother was that dumb."
It was in December 2020 that Farwell said Birchmore told him that she was pregnant with what she believed was Matthew Farwell's baby. Shortly after, he met his brother at a Brockton bar.
"I have a problem and I need your help," Matthew Farwell said, according to William, but they didn't finish the conversation because other police officers walked in.
On Jan. 5, 2021, about a month before Birchmore died, she texted William Farwell to ask if he would visit the baby.
"This is a horrible idea, and to be honest, I can't and won't be in the middle of it," Farwell responded.
Farwell testified that the last time he saw Birchmore was on Jan. 20 when he visited her after leaving a bar around midnight. He said he doesn't remember anything about the visit because he "drank to the point of intoxication" and "blacked out."
William Farwell said that when he was told Birchmore had died by suicide, he texted his brother.
"He said something to the effect of, 'OK,'" Farwell testified.
Ten days later, Farwell said he was contacted by Massachusetts State Police. He met with Sgt. John Fanning and Trooper Matt Dunne in a parking lot to discuss Birchmore.
Farwell testified that Fanning, who he had known since childhood, said he would try to leave him out of his report.
"He told me I was not a suspect and that there were no suspects," Farwell said.
He also recalled Fanning saying, "I need this like I need a f---ing bullet in the head."
Afterward, Farwell said they had their first conversation about sexual relations with Birchmore.
"Matty, tell you didn't f--- that girl when she was under 16," William Farwell recalled saying. "He said, 'no.'"
Matthew Farwell's attorney did not deny her client and Birchmore had an affair, but she said Farwell never thought the baby was his and when he broke up with Birchmore, she killed herself. DNA testing later confirmed the father of Birchmore's unborn child was Jason Pickard, a U.S. Army recruiter who was also having a sexual relationship with Birchmore. He also testified in the trial under an immunity agreement.
During cross-examination, William Farwell admitted to having sex with Birchmore in his police cruiser. He acknowledged it's a crime that he has immunity for thanks to his deal with the government.
The defense also asked Farwell about his testimony that his brother "wiped" his phones. They compared it to former New England Patriots quarterback Tom Brady destroying his phone during the DeflateGate scandal. Farwell said during cross-examination that he didn't know for sure if Farwell actually wiped his phone.
The prosecution has said they could potentially rest their case Wednesday. If convicted, Matthew Farwell faces a mandatory sentence of life in prison.
