Sandra Birchmore's ex-boyfriend, witnesses from medical examiner's office testify in Matthew Farwell trial

The defense is now presenting its case in Matthew Farwell's murder trial, with one of Sandra Birchmore's ex-boyfriends and the Massachusetts chief medical examiner testifying on Thursday. 

The prosecution rested Wednesday after calling 38 witnesses to try and prove that Farwell, a former Stoughton police officer, is guilty of killing the 23-year-old and her unborn baby in her Canton apartment on Feb. 1, 2021. The two met when Birchmore was a 13-year-old cadet in the Stoughton Police Department's youth explorers program. 

Farwell has pleaded not guilty to federal charges of killing a witness or victim and causing the death of an unborn child. He faces a mandatory sentence of life in prison if convicted.

Sandra Birchmore's ex-boyfriend testifies

Sandra Birchmore's ex-boyfriend William Kilroy was first on the stand Thursday morning. They met at Massasoit Community College in 2016.

They dated for a few months, but stopped as Birchmore struggled to deal with the deaths of her mother and grandmother, Kilroy testified.

"During this time of loss, did she relay suicidal thoughts to you?" the defense asked.

"At times, yes," Kilroy said.

In 2018, Birchmore told Kilroy that she was had been pregnant with his baby, but had a miscarriage. Kilroy said she made a threat about suicide.

"She said she was going to commit suicide and put me in the note as one of the reasons," Kilroy said.

During cross-examination, the prosecution asked Kilroy if Birchmore ever actually attempted suicide during that time, and Kilroy said she did not.

Witnesses from medical examiner's office testify

Dr. Mindy Hull, the chief medical examiner, took the stand briefly after and testified that all her technicians are trained in forensic pathology. Birchmore's death was initially ruled a suicide by the offfice and then changed years later to "undetermined."

The next witness was Caitlyn Bulger, a technician with the office. She went to Birchmore's Canton apartment after she was found dead.

"Home is unkempt, no trauma being reported other than ligature mark. No foul play at the time of report," Bulger's report said.

Matthew Farwell trial

Prosecutors on Wednesday used their final witness, a digital forensics expert named Jessica Hyde who also testified in the Karen Read trials, to present their theory that Farwell strangled Birchmore and staged it as a suicide to conceal their years-long sexual relationship that allegedly began when she just 15 years old. 

Hyde testified that on Feb. 1, Birchmore's phone locked for the final time at 9:13 p.m. One minute later, a masked Farwell was seen on surveillance video entering her apartment building. 

At 9:18 p.m., her camera app was opened. At 9:40 p.m. the phone records eight steps, and 20 seconds later, a button is touched. That's the last user activity ever documented on her phone, and Farwell isn't seen leaving her apartment until nearly three minutes later.

WBZ-TV legal analyst Jennifer Roman says the prosecution put on a strong case with a tight timeline, and the defense will have to show that Birchmore was suicidal, despite being excited about the pregnancy.

"They're going to try to get around that to say this was an impulse reaction by Sandra Birchmore," Roman said. "She was so upset and distraught that in that moment she became suicidal, and she was a young woman who had struggled with mental health, and so therefore it wasn't unusual or unexpected that this might happen for her."

The defense started presenting that argument Wednesday with their first witness who testified that Birchmore told him in 2017 that she had tried to kill herself.