A new prosecution witness has cast serious doubt on Lindsay Clancy’s claim that a male voice commanded her to kill her three children, arguing that the way she described the alleged hallucination was highly unusual and more consistent with an intrusive thought than a true command hallucination.
The testimony came Monday as prosecutors presented their rebuttal case in Clancy’s closely watched murder trial, bringing the proceedings another step closer to closing arguments and a verdict.
Psychologist Kirk Heilbrun, who interviewed Clancy for roughly 10 hours over three days in April, told jurors that he found some evidence suggesting she may have experienced an acute psychotic episode. But he said one of the central pieces of that claim — Clancy’s assertion that she heard a male voice telling her to kill herself and her children — raised significant questions.
According to Heilbrun, Clancy never reported hearing the voice before the killings and did not report hearing it afterward.
That timing, he testified, was highly unusual.
Heilbrun said he is particularly cautious when someone reports a psychiatric symptom that appears only during the commission of a crime, explaining that such a claim can potentially provide a way for a defendant to lessen their responsibility.
While he acknowledged that such an experience is possible, he characterized the pattern in Clancy’s case as extremely rare.
Clancy, 36, has pleaded not guilty by reason of insanity to three counts of murder in connection with the deaths of her children — 5-year-old Cora, 3-year-old Dawson and 8-month-old Callan — at the family’s Duxbury, Massachusetts, home on Jan. 24, 2023.
The killings are not disputed by the defense.
Instead, the central question at trial has been why Clancy killed her children and whether she understood that what she was doing was wrong.
The defense has argued that Clancy was suffering from postpartum psychosis and was experiencing hallucinations and delusions that overwhelmed her ability to understand the wrongfulness of her actions.
A defense psychiatric expert previously testified that Clancy was “frankly psychotic” and believed she had experienced command hallucinations that instructed her to kill her children and herself.
Heilbrun offered a dramatically different interpretation.
He testified that Clancy’s accounts of the alleged male voice changed over time and did not consistently resemble the behavior of a command hallucination.
Instead, he said the descriptions were more consistent with an intrusive thought — something Clancy had reportedly been experiencing for months.
One detail after the killings particularly stood out to Heilbrun.
Following her suicide attempt, Clancy spoke with her then-husband, Patrick Clancy. According to the psychologist, the first thing she told him was that she had attempted to kill herself.
Heilbrun suggested that if Clancy truly believed she had been commanded by an external voice to commit the killings, he might have expected her immediate explanation to focus on the alleged command.
Instead, she reportedly described what she had done herself.
The psychologist also presented an explanation for the killings that differed sharply from the defense’s theory.
He described the case as an example of “altruistic filicide,” a term used to describe a parent killing their children because they believe they are protecting them from suffering.
According to Heilbrun, Clancy was deeply attached to her children and struggled with being separated from them, whether because of work, school or other activities.
He testified that once Clancy decided to end her own life, she faced what she perceived as a choice about what would happen to her children after she was gone.
His conclusion was that she did not want to leave them behind.
Instead, he said, she believed they would suffer without her and decided to take them with her.
That interpretation directly supports the prosecution’s broader argument that Clancy’s actions were deliberate rather than the product of a complete break from reality.
Prosecutors have acknowledged that Clancy experienced significant mental health problems but maintain that she nevertheless understood the difference between right and wrong when she killed her children.
The prosecution has characterized the killings as intentional, rational and swift.
The defense, meanwhile, continues to argue that Clancy was in the grip of postpartum psychosis and was not criminally responsible for her actions.
But Heilbrun’s testimony was not the only dramatic development in court Monday.
His testimony suddenly became a major courtroom issue after he referred to Clancy’s Roman Catholic upbringing while discussing the phrase “Go to God,” which Clancy reportedly said as she strangled her children.
Heilbrun began discussing whether Clancy understood that suicide was considered a mortal sin within Catholic teaching.
The defense immediately objected, and attorney Kevin Reddington later asked Judge William Sullivan to declare a mistrial.
Reddington argued that the reference to religion amounted to improper prosecutorial conduct and had unfairly injected Catholic beliefs into the trial.
Prosecutors pushed back, saying the reference was not intentional. They noted that they had not specifically asked Heilbrun about religion and argued that his comment had not been deliberately elicited.
Judge Sullivan ultimately rejected the defense’s request for a mistrial.
Instead, he ordered jurors to disregard the psychologist’s comments concerning Clancy’s religious upbringing and Catholic theology.
The judge emphasized that the subject was inappropriate for the jury to consider and instructed jurors to strike that portion of the testimony from their deliberations.
Several jurors appeared to acknowledge the instruction.
The religious issue has now surfaced twice during the trial. The previous week, prosecutors asked Clancy’s former mother-in-law whether she knew that murder was considered a mortal sin. Judge Sullivan immediately intervened and told jurors not to consider that question.
With the mistrial request denied, the trial is continuing toward its final stage.
Prosecutors are expected to finish presenting their rebuttal witnesses Tuesday, although the schedule could change. Closing arguments are currently expected Wednesday.
And after weeks of testimony from family members, psychiatrists, psychologists and other experts, jurors will ultimately have to decide one of the most consequential questions in the case:
Was Lindsay Clancy suffering from a psychiatric condition so severe that she could not understand the wrongfulness of killing her three children — or did she know exactly what she was doing?
The competing interpretations of her alleged hallucinations may become one of the most important pieces of evidence they consider.
