Prosecution Psychologist: Lindsay Clancy Knew Killings Were Wrong

A forensic psychologist testified Monday that Lindsay Clancy lacked acute psychosis when she strangled her three children in January 2023. He said she acted to prevent them from suffering after her own planned suicide.

Psychologist Rules Out Acute Psychosis in Clancy Murder Trial

A forensic psychologist told a Massachusetts jury Monday that Lindsay Clancy did not have acute psychosis when she killed her three children in January 2023, but instead took their lives to spare them suffering after she intended to take her own, Courthouse News Service reports.

Dr. Kirk Heilbrun, testifying as a prosecution witness, said he rejected the defense claim that Clancy was in the grip of command hallucinations at the time of the killings. Clancy had told evaluators she heard a voice instructing her to "kill the children so you can kill yourself." Heilbrun said he did not find her account credible.

"The way she described this as happening is that she heard a voice that she'd never heard before, experienced a hallucination and she's never experienced it since. But she only experienced it for the 18 minutes or so that it took to kill the children," Heilbrun testified. "To put it mildly, that would be a very, very unusual pattern or manifestation of how this kind of thing comes about. Very unusual."

Heilbrun said Clancy killed the children because she wanted to die but did not want to leave them behind. He recounted that during the strangulations she said, "Go to God, baby. Go to God" — part of what he described as her expectation that she and the children would reunite in heaven.

Heilbrun also referenced Clancy's Catholic faith during testimony, prompting defense attorney Kevin Reddington to move for a mistrial. Judge William Sullivan denied the motion but later instructed the jury to disregard the religious reference, calling it "an absolutely inappropriate area of testimony."

Key dispute: criminal responsibility

The central question at trial is not whether Clancy killed her children — Reddington does not contest that — but whether she can be held criminally responsible. The defense argues she was suffering from postpartum psychosis, a rare and severe mental illness associated with hormonal changes, sleep deprivation, and the physical stress of childbirth. Clancy, 36, has pleaded not guilty to murder charges in the deaths of Callan, Dawson, and Cora Clancy, aged 8 months to 5 years old.

After killing the children, Clancy jumped from a second-floor window and has been paralyzed from the waist down since.

Heilbrun is the latest in a series of prosecution witnesses to conclude that, while Clancy was mentally ill at the time, she retained the capacity to understand that what she was doing was wrong. On Friday, forensic psychiatrist Dr. Avram Mack testified he found no evidence of mania, hypomania, or psychosis leading up to the killings, describing her condition as a continuation of a months-long depression during which she was able to control impulses and distinguish right from wrong.

Heilbrun did, however, diagnose Clancy with bipolar 2 disorder — a condition marked by cycles of depression and hypomania, less intense than the full mania seen in bipolar 1. He acknowledged the diagnosis was difficult to reach, citing "all the diagnoses in the records and all the symptoms that she experienced."

Defense witnesses described a different picture

Earlier in the trial, defense witnesses offered sharply contrasting assessments. Dr. Phillip Resnick, a forensic psychiatrist and expert in filicide — the killing of a child by a parent — testified Friday that Clancy was "clearly psychotic" on the day of the killings and not in control of her actions. "It was almost like she was a puppet and someone else was pulling the strings," Resnick said.

Psychologist Paul Zeizel similarly concluded that Clancy "had no appreciation for the wrongfulness of her act."

The jury also heard earlier in the proceedings that Clancy had sought mental health treatment from multiple providers and had admitted herself to a psychiatric hospital before the killings. Prosecutors contend she planned the attack and arranged for her husband to leave the house by sending him to pick up medication for one of the children and dinner for the family.

Closing arguments are expected later this week.

--- If you or someone you know needs help, the national suicide and crisis lifeline in the U.S. is available by calling or texting 988.

Source: Courthouse News Service