October 30: Defense Psychiatrist Testifies as Matthew Farwell Trial Examines Sandra Birchmore’s Mental Health

On Friday, October 30, 2026, the defense in the federal trial of former Stoughton police detective Matthew Farwell called forensic psychiatrist Dr. Melissa Piasecki to testify. Farwell is accused of killing Sandra Birchmore in 2021 and causing the death of her unborn child. He has pleaded not guilty. Defense attorneys contend Birchmore died by suicide; federal prosecutors allege Farwell killed her and tried to make the death appear self-inflicted. The expert’s appearance means jurors are now hearing another side of the dispute about Birchmore’s mental health and the cause of her death. It is not a new judicial finding about how she died.

Why It Matters

A mental health history can be relevant to competing explanations of a death, but it does not determine the manner of death by itself. The jury must weigh the expert’s analysis alongside forensic evidence, medical findings, communications, witness accounts and the applicable law. Sandra was a young woman who had hopes for her pregnancy and future, not simply a medical chart. Readers deserve to understand both sides’ evidence without confusing an advocate’s theory, an expert’s opinion and a finding of fact.

Go Deeper | The October 30 Court Record

What happened in the courtroom Friday

Boston 25 News’ reporter Bob Ward described the jury entering federal court in South Boston shortly after 1 p.m. Eastern. At approximately 1:08 p.m., the defense called Dr. Melissa Piasecki. Its contemporaneous reporting first covered her credentials and work researching suicide risk and prevention, then noted that she reviewed Birchmore’s medical and mental-health records, school records, electronic messages, social-media material, bank records, FBI reports and testimony in this trial.

Those are the records the reporter said the defense expert examined. Their inclusion in an expert review does not make every assertion within them true, and it does not mean the jury has accepted her conclusions. At this checkpoint, the expert’s full testimony, cross-examination and any ruling on its weight were not available as a certified transcript.

The question the defense is asking jurors to consider

Farwell’s defense argues Birchmore died by suicide after the breakdown of their relationship. Prosecutors allege Farwell killed her to keep their relationship from being exposed, then staged the scene. They differ both about motive and about how to interpret medical and physical evidence. A forensic psychiatrist can address a person’s history and risk factors, but the ultimate legal decision is the jury’s, not the witness’s.

What Thursday’s witnesses discussed

On October 29, the defense called Sandra’s former boyfriend William Kilroy and other witnesses. Kilroy described struggles he remembered after deaths in her family and said Birchmore had discussed suicide during the period when he knew her. That testimony concerns what a witness remembered years earlier. It does not by itself establish her state of mind on the day she died. Read our separately dated October 29 report.

What the prosecution had already presented

Federal prosecutors rested their case earlier in the week, after presenting witness testimony and forensic material. Jurors have heard testimony about digital communications, medical findings, a contested ligature, and competing interpretations of the scene. The prosecution’s theory is that Farwell killed Birchmore, who was pregnant, and arranged the scene to resemble suicide. The defense disputes that conclusion.

Our previous articles separate medical examiner opinions, forensic testimony, friends’ accounts and digital records by the dates they were actually introduced. A later expert witness should not be silently added to an October 27 or 29 article as though the testimony had already been heard.

What a forensic psychiatrist can and cannot establish

The role of this witness is different from that of the medical examiners and forensic specialists. Reviewing mental-health history and records may inform an assessment of factors associated with suicide risk. It does not independently establish whether a homicide occurred, what physically happened in the apartment, or whether Farwell committed the charged offenses. Those questions require evaluation of the total evidence.

Some descriptions from Thursday and Friday involve private mental-health information. We are reporting only what is necessary to explain the courtroom dispute and are not reproducing personal diary passages or graphic descriptions.

What Happens Next

The defense is presenting its case. The next reliable report should establish what Dr. Piasecki ultimately testified, what questions federal prosecutors asked on cross-examination, whether further witnesses are called, and the judge’s next steps. As of this publication checkpoint, there is no verified verdict. The case remains an active federal trial, and Farwell retains the presumption of innocence.

Readers can follow the main case page, trial tracker, and court-document collection for the primary chronology.

October 30 Afternoon Update | Psychiatrist Explains Her Opinion, Government Tests Its Limits

Reporting update: October 30, 2026, after the initial 1:20 p.m. Eastern checkpoint. Later Boston 25 News courtroom reporting provided the substance of Dr. Melissa Piasecki’s testimony. This section was added after the earlier initial report; it does not change what was known at that earlier checkpoint.

What Piasecki told the jury

The defense forensic psychiatrist said her review of Sandra Birchmore’s records revealed factors that she believes raised the risk of death by suicide. She discussed earlier family bereavements, mental-health treatment and financial pressures. She also addressed a note written in 2017, years before Birchmore’s 2021 death, and explained why she considered the earlier material relevant to her risk assessment.

Piasecki described the importance Birchmore placed on her relationship with Matthew Farwell and offered an opinion about how she might have experienced losing that relationship. These are the expert’s interpretations of historical records, not direct testimony about what physically happened in Birchmore’s apartment in February 2021.

What the government challenged

During cross-examination, prosecutors emphasized that Piasecki had not personally met Sandra Birchmore and was forming her conclusions from files and other records. The government’s position is that Farwell killed her and made her death look like suicide; the defense disputes that claim. The jury has heard other witnesses describe Sandra as hopeful about her pregnancy and future, as well as forensic testimony concerning the scene and physical evidence. The expert’s assessment is one part of this disputed record.

What the testimony does not prove

A statistical or clinical assessment of a person’s vulnerability does not determine the manner of their particular death. Earlier thoughts or statements cannot by themselves establish that a death was suicide, and statements about optimism cannot independently prove homicide. Each claim must be considered in the context of the complete case and the court’s instructions.

What Happens Next

Boston 25 reports that further defense witnesses are expected Monday, November 2. The report raises the possibility of jury deliberations later the following week, but that is not a verified final schedule. No verdict has been returned as of this reporting checkpoint. Farwell has pleaded not guilty and remains presumed innocent unless convicted.

Boston 25 News October 30, 3:58 p.m. EDT: Full afternoon testimony report.

Footnotes | Source and Time Record

Chronology and update note: The initial October 30 story was based on courtroom reporting available through approximately 1:20 p.m. Eastern. The separately labeled afternoon section above was added after Boston 25 published more of the testimony at 3:58 p.m. EDT. We do not claim that all defense testimony finished, closing arguments occurred, or the jury reached a verdict. No recreated crime-scene images, invented quotations or graphic testimony are reproduced. Farwell remains presumed innocent unless convicted. Every name has a story.

Like this story