Matthew Farwell’s own lawyer told the jury Friday that he was in Sandra Birchmore’s apartment the night she died. “I went there to break up with her,” Farwell told investigators, according to defense attorney Kimberly Stevens’s opening statement as reported by CBS Boston. “I told her that’s not my baby. The timeline doesn’t work.”
That is the defense theory in two sentences: Farwell ended the relationship, told Birchmore the baby was not his, and “in an impulsive act of despair, she took her own life,” Stevens said. It also raises a question about the rules of evidence that could shape the next five weeks. A defendant’s own words can be used against him. Can his lawyer use them for him? Here is how the federal rules handle it. Farwell has pleaded not guilty and is presumed innocent.
What each side told the jury
The prosecution. Assistant U.S. Attorney Torey Cummings told jurors there were more than 40,000 messages between Farwell and Birchmore, including some discussing strangling and choking, CBS reported. She said Farwell became “enraged” after a Stoughton police dispatcher told him a friend of Birchmore’s had reported the relationship, and told Birchmore, “you have no idea how bad what she did is.” “Twelve days after the defendant sent those messages, Sandra was dead,” Cummings said. “She could end his life with the information she had, so he was going to end hers first.” She also told jurors that State Police and the Norfolk County District Attorney’s office “did very little to actually investigate the death.”
The defense. “Matthew Farwell is a man who had an affair,” Stevens said, according to CBS. “He’s human. Matthew Farwell did not kill Sandra Birchmore.” She pointed to Birchmore’s search for “what color is the suicide ribbon?” on the day she died, texts suggesting she was struggling, and a bank balance of less than $3. “That’s a window into her mental state,” Stevens said. She told jurors Farwell met voluntarily with investigators, and that it took three and a half years for the government to look at the case.
The narrowed dispute
The defense opening did something important: it did not dispute that Farwell went to the apartment on February 1, 2021. Prosecutors have said building video shows him entering and leaving that night. The fight is now over what happened inside, and whether Birchmore’s death was a homicide at all.
That matters because of what the government must prove on the main count, killing a witness under 18 U.S.C. § 1512(a)(1)(C): that Farwell killed Birchmore, and that he did it to keep information about federal crimes from reaching law enforcement. If the jury has a reasonable doubt that this was a killing, the motive evidence never comes into play.
The rule: a defendant’s words can be used against him
Under Federal Rule of Evidence 801(d)(2)(A), a statement is not hearsay if it “is offered against an opposing party” and “was made by the party in an individual or representative capacity.” That is why prosecutors can introduce what a defendant told police.
The key word is “against.” The rule lets the government use Farwell’s statements against Farwell. It does not, by itself, let the defense introduce Farwell’s own out-of-court statements to prove they are true. If the defense wants the jury to rely on “I told her that’s not my baby,” the usual routes are:
- The government plays it first. If prosecutors introduce part of Farwell’s interview, Rule 106, the “rule of completeness,” lets the defense require the introduction “at that time, of any other part … that in fairness ought to be considered at the same time,” and it may do so “over a hearsay objection.”
- Another witness heard it. If an investigator who interviewed Farwell testifies, the defense may try to bring out the rest of the conversation on cross-examination, subject to the same rules.
- Farwell testifies. He can tell the jury himself, and then be cross-examined. He has an absolute right not to testify, and the jury cannot hold silence against him.
A lawyer’s opening statement is a promise about what the evidence will show. How the defense delivers on this one, through the government’s evidence or through Farwell himself, is one of the things to watch.
Birchmore’s words: both sides will use them
The same hearsay rules apply to what Birchmore wrote and said. Federal Rule of Evidence 803(3) allows “[a] statement of the declarant’s then-existing state of mind (such as motive, intent, or plan) or emotional, sensory, or physical condition (such as mental feeling, pain, or bodily health).”
That exception is likely to carry both cases. The prosecution will point to Birchmore’s plans for the baby and her search for baby showers in her last hour as evidence of a woman planning a future. The defense will point to texts saying she was stressed and could not sleep, and to the suicide-ribbon search, as evidence of a woman in crisis. Judge Denise Casper has already ruled that Birchmore’s diary entries and testimony from people close to her may come in.
The judge has also allowed the government to use some of Birchmore’s statements under a different rule, Federal Rule of Evidence 804(b)(6), forfeiture by wrongdoing, which covers a statement “offered against a party that wrongfully caused … the declarant’s unavailability as a witness, and did so intending that result.” We covered that ruling in our tracker.
What comes next
- Tuesday, October 13: testimony begins, 9 a.m. to 4 p.m.
- The schedule: about five weeks, Judge Casper said.
- No cameras: federal court does not allow broadcast or photography.
Frequently asked questions
What is Matthew Farwell’s defense?
That Sandra Birchmore died by suicide. In opening statements, his lawyer said Farwell went to her apartment to break up with her and told her the baby was not his, and that she then took her own life.
Can a defendant’s statements to police be used at trial?
Yes, against him. Under Federal Rule of Evidence 801(d)(2)(A), a party’s own statement offered against that party is not hearsay. A defendant generally cannot introduce his own out-of-court statements to prove they are true unless an exception applies, such as the rule of completeness in Rule 106.
Does Matthew Farwell have to testify?
No. He has a constitutional right not to testify, and the jury may not hold it against him if he does not.
When does testimony start in the Farwell trial?
Tuesday, October 13, 2026, in federal court in Boston.
Sources: CBS Boston, October 9, 2026, quoting both opening statements; NBC10 Boston and WHDH, October 9, 2026. Federal Rules of Evidence 106, 801(d)(2), 803(3) and 804(b)(6) read at the Legal Information Institute. Charge described from the superseding indictment as reviewed for our trial preview. Opening statements are not evidence. Matthew Farwell is presumed innocent. General information about the law, not legal advice.