BOSTON (WHDH) - William Farwell, the twin brother of defendant Matthew Farwell, testified in his federal murder trial Monday in exchange for immunity, meaning he can not be charged with any crimes he admits to while on the stand.
Matthew Farwell is charged with killing 23-year-old Sandra Birchmore and her unborn child and staging the death to look like a suicide. Prosecutors allege Farwell killed her to stop her from exposing federal crimes, including sexual exploitation of a child. They claim Farwell had been grooming her for sex since she was 15 years old and part of the Stoughton Police Explorers mentoring program.
William continued testimony on Tuesday. He previously testified he began having sex with Sandra Birchmore in 2019, only learning later that his brother was sleeping with her earlier.
William testified that Birchmore told him she started having sex with his brother when she was just 15. He said he didn’t believe it, saying in court, “The first reason was I didn’t necessarily believe her, and the second was I didn’t think my brother was that dumb.”
When Birchmore became pregnant and told him Matthew was the father, William said, ” You two need to figure this (expletive) out. This is a horrible idea. To be honest, I can’t or won’t be in the middle of it.”
Dr. William Smock, a strangulation expert, also took the stand on Tuesday. He testified that there was evidence of murder, not suicide.
Dr. Smock testified he saw a defensive scratch on crime scene photos. He said marks on Birchmore’s body showed Birchmore clinging to the strap around her neck and trying to move her nose and mouth for air.
Dr. Smock also testified that Birchmore’s broken necklace under the strap, which state and local investigators didn’t find, is something he’s never seen in a suicide. He said Birchmore’s tangled hair in the strap is another key clue. He said that is one of the biggest red flags of a homicide.
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