“The Trial of Lindsay Clancy”: 20/20 Reports September 4 2026

ABC News turns to one of the most difficult criminal cases to reach a Massachusetts courtroom in recent years with “The Trial of Lindsay Clancy,” an all-new special edition of 20/20 airing Friday, September 4, 2026, from 9:00-10:00 p.m. EDT on ABC.

The special arrives only hours after Judge William Sullivan declared a mistrial in Clancy’s prosecution for the deaths of her three children. After weeks of evidence and seven days of deliberations, jurors could not agree on the question at the center of the case: whether Clancy committed murder with criminal responsibility or whether severe mental illness left her unable to appreciate the wrongfulness of killing her children.

20/20 examines the deaths of 5-year-old Cora Clancy, 3-year-old Dawson Clancy and 8-month-old Callan Clancy, the psychiatric crisis that preceded them, the prosecution’s case for premeditated murder and the defense argument that Lindsay Clancy was suffering from postpartum psychosis. The broadcast also comes at a point when the criminal case remains unresolved. A mistrial is not an acquittal, and Clancy continues to face the charges while prosecutors consider their next move.

Lindsay Clancy and Her Family Before the Killings

Lindsay Clancy was a labor and delivery nurse living with her husband, Patrick Clancy, and their three children in Duxbury, a coastal community south of Boston. Their youngest child, Callan, was born in May 2022. In the months after his birth, Lindsay began experiencing serious mental-health problems that would become a central part of both the criminal case and later civil litigation.

The dispute at trial was not over whether Clancy had been ill. The prosecution and defense agreed that she had experienced significant psychiatric problems. The disagreement concerned the nature and severity of that illness, whether she was psychotic on January 24, 2023, and whether her condition met Massachusetts’ standard for a lack of criminal responsibility.

By the fall of 2022, Clancy was seeking treatment for anxiety, depression, insomnia and other symptoms. Her treatment became complex. Evidence at trial showed that she received more than 30 prescriptions between September 2022 and January 2023, although that did not mean she was taking all of those medications at the same time. Her clinicians changed medications and dosages as they attempted to manage her symptoms.

The medications discussed in records included antidepressants, anti-anxiety drugs, sleep medications, mood stabilizers and antipsychotic drugs. Among them were sertraline, fluoxetine, trazodone, mirtazapine, clonazepam, diazepam, quetiapine, zolpidem and lamotrigine. The defense portrayed the treatment history as evidence of a psychiatric system struggling to identify what was happening to Clancy. Prosecutors argued that extensive treatment records also mattered because clinicians who saw her before the killings had not documented the type of psychosis the defense said was present on January 24.

A Mental-Health Crisis Deepens

By December 2022, Clancy’s problems had become more serious. Her husband later told investigators that she had experienced suicidal thoughts and thoughts about harming the children. She sought emergency and psychiatric care, and Patrick became involved in efforts to obtain treatment for her.

On January 1, 2023, Clancy admitted herself to McLean Hospital in Belmont. She remained there for about five days. According to the prosecution’s account of her medical history, she was discharged without clinicians determining that she represented an immediate danger to herself. The significance of that hospitalization became part of the later debate over whether the severity of her condition had been missed.

There were also signs that appeared inconsistent with an acute psychotic break. Two days before the killings, the Clancys visited friends for dinner. A family friend later described Lindsay as appearing fairly normal. On January 23, according to prosecutors, she wrote in a note on her phone that she had “a touch of postpartum anxiety” connected with returning to work.

Those details acquired different meanings at trial. Prosecutors used them to challenge the claim that Clancy had entered a psychotic state. The defense argued that psychiatric illness does not require a patient to appear psychotic to every person at every moment and that Clancy’s months of treatment, suicidal thinking, dissociation and medication changes showed a woman in a severe psychiatric crisis.

January 24, 2023 Began as an Ordinary Family Day

The morning of January 24, 2023, gave little indication of what was to come. Clancy took Cora to a medical appointment. She spent time outside with the children in the snow and sent photographs to family members. Patrick Clancy later characterized it as a good day.

During the afternoon, Lindsay searched for information about children’s laxatives. Cora had been having stomach problems, and a doctor had recommended medication. Clancy contacted a CVS pharmacy to determine whether it had the product and discussed getting takeout with Patrick.

One detail became critical to the prosecution’s theory. Clancy used a mapping application to check the route between the family home and the restaurant where Patrick would collect dinner. Prosecutors argued that she was determining how much time she would have alone with the children. The defense disputed the inference, maintaining that the errands arose from normal family needs and that Clancy had been anxious about being left alone.

At about 5:15 p.m., Patrick left the house. His trip included a stop at CVS followed by a visit to the restaurant. He left Lindsay at home with Cora, Dawson and Callan.

Cora, Dawson and Callan Are Killed

What happened while Patrick was away was not disputed in its central fact. Lindsay Clancy killed all three children.

The evidence showed that the children were taken into the basement and strangled with exercise bands. Prosecutors said Clancy separated Dawson from Cora and Callan and placed bands around the children’s necks. The children were left in the basement with the bands still around them.

At one point during Patrick’s trip, he called home. Lindsay missed his call and returned it. Their conversation lasted about 14 seconds. Patrick detected nothing during the exchange that caused him to abandon his errands and return home. Prosecutors viewed that interaction as important evidence that Clancy retained enough control to speak to her husband without alerting him to what was taking place.

After attacking the children, Clancy went upstairs. The prosecution said she obtained a knife, entered the second-floor bedroom, locked the door, took or attempted to take medication and cut herself before going out a window in an attempt to end her own life. The fall caused spinal injuries that left her paralyzed from the waist down.

The sequence took place during the short period in which Patrick was away from the house. That compressed timeline would become one of the prosecution’s strongest arguments for planning and one of the defense’s starkest illustrations of what it described as a sudden psychotic episode.

Patrick Clancy Returns to a Silent House

Patrick returned at about 6 p.m. The house was quiet. He found the bedroom door locked and, after gaining access, discovered blood and an open window. He then found Lindsay outside on the ground beneath it.

First responders were called. Patrick asked Lindsay where the children were and was directed toward the basement. Cora, Dawson and Callan were found there. Emergency personnel began attempts to save them.

Cora and Dawson could not be revived. Callan still had a pulse restored during efforts to resuscitate him and was transferred for further treatment. He had suffered catastrophic injuries from strangulation and never recovered brain function, according to the defense’s early account of his medical condition.

Callan was pronounced dead at Boston Children’s Hospital on January 27, 2023, three days after the attack. What had begun as an investigation into the deaths of two children became a case involving all three Clancy children.

Clancy Survives and a Criminal Case Begins

Clancy survived her fall but sustained life-changing injuries. As she recovered in the hospital, investigators began reconstructing the events inside the house and examining her electronic devices, medical records, communications and psychiatric history.

An arrest warrant was issued on January 25. The initial allegations included homicide, strangulation and assault charges. When Clancy became capable of communicating after the incident, prosecutors said one of the questions she wrote on a whiteboard was whether she needed an attorney. The prosecution later used evidence of that kind as part of its argument that Clancy understood the legal significance of what had occurred.

The case took another turn on February 6. During a conversation with Patrick in the presence of a psychologist retained by her defense, Clancy described what she said had happened in the house. According to the prosecution’s account of the conversation, she told Patrick that she had heard a man’s voice telling her to kill the children and herself because it was her last chance.

That reported voice became one of the most important pieces of evidence in the eventual trial. To the defense, it was a command hallucination produced by psychosis. To prosecution experts, aspects of Clancy’s description did not fit the pattern they would expect from a genuine psychotic hallucination.

Patrick Clancy Publicly Forgives His Wife

The case contained another unusual element: Patrick Clancy’s response to the deaths of his children and the prosecution of his wife.

Four days after the attacks, Patrick issued a statement through a fundraising page. He asked people to forgive Lindsay as he had. He wrote about Cora, Dawson and Callan and the individual personalities of the three children while describing his grief at losing them.

Patrick’s position remained significant years later. He testified during Lindsay’s 2026 trial and described her mental-health decline and the events surrounding the killings. His testimony offered jurors an account from the person who had lived with Clancy throughout her deterioration and who had returned home to discover the aftermath.

His forgiveness did not determine the legal issue before the jury. Massachusetts prosecutors were required to decide whether the evidence supported criminal charges regardless of the family’s position. It did, however, make the case different from many homicide trials, where victims’ relatives appear before a jury seeking a conviction.

Murder Charges Move to Superior Court

A Plymouth County grand jury indicted Clancy on September 15, 2023. The indictment brought six charges connected with the deaths of Cora, Dawson and Callan. She was arraigned in Plymouth Superior Court the following month and pleaded not guilty.

The case then moved through years of preparation. The physical facts of the killings were not expected to form the main battlefield. The defense acknowledged that Clancy had killed her children. The issue was criminal responsibility.

Under Massachusetts law, the jury had to consider more than whether Clancy had a psychiatric diagnosis. Mental illness alone does not remove criminal responsibility. The question concerned whether, because of mental disease or defect, she lacked the substantial capacity to appreciate the wrongfulness of her conduct or to conform her conduct to the requirements of law.

That distinction transformed the trial into a contest between competing interpretations of the same woman and many of the same events.

Prosecutors Argue That the Killings Were Planned

When the trial opened in the summer of 2026, prosecutors presented the killings as a sequence of deliberate choices rather than an uncontrollable act produced by psychosis.

They emphasized Clancy’s actions before Patrick left. She researched the route to the restaurant, confirmed the pharmacy stop, arranged the takeout order and knew how long the errands would take. The prosecution argued that those actions created a window in which she could be alone with the children.

The Commonwealth also pointed to what happened during and after the killings: the children were taken to the basement, exercise bands were used to strangle them, Clancy communicated with Patrick while he was out, and she attempted suicide after killing them. To prosecutors, the sequence demonstrated purposeful conduct.

The prosecution did not need to prove that Clancy had no mental illness. Its case was that depression, anxiety or another psychiatric disorder did not mean she lacked criminal responsibility. Its experts argued that she remained aware that killing her children was wrong.

The Defense Builds Its Case Around Postpartum Psychosis

Defense attorney Kevin Reddington presented a different explanation. He argued that Clancy’s actions could not be understood without the psychiatric collapse that preceded January 24.

The defense traced months of worsening symptoms, medication changes, suicidal thoughts, hospital treatment and attempts by Lindsay and Patrick to obtain help. Clancy’s lawyers argued that she suffered from bipolar disorder with postpartum psychosis and that the health-care system failed to identify the condition before three children died.

Forensic psychologist Dr. Paul Zeizel, who evaluated Clancy for the defense, testified that she had bipolar disorder and postpartum psychosis. He concluded that her condition prevented her from appreciating the wrongfulness of killing her children.

The defense also called Dr. Phillip Resnick, a forensic psychiatrist with extensive experience studying parents who kill their children. Resnick had previously testified in the case of Andrea Yates, the Texas mother whose murder convictions for drowning her five children were overturned before she was found not guilty by reason of insanity at a second trial.

Resnick concluded that Clancy was psychotic when she killed Cora, Dawson and Callan. He described her reported experience as a command hallucination in which a male voice instructed her to kill the children. According to Resnick, Clancy described feeling that an outside force had taken control of her body.

Prosecutors Challenge the Command-Hallucination Account

The Commonwealth countered the defense experts with specialists who questioned both the postpartum-psychosis diagnosis and Clancy’s description of the voice.

Forensic psychologist Dr. Kirk Heilbrun testified that Clancy suffered from serious depression and dissociation but was not psychotic. He concluded that she retained an understanding that killing her children was illegal. He also questioned the reported hallucination because Clancy described the voice as emerging during a limited period surrounding the killings rather than as part of a broader pattern of hallucinations.

Forensic psychiatrist Dr. Gregory Saathoff also challenged Clancy’s account. He testified about interviews in which she described the male voice and raised questions about the timing, characteristics and abrupt disappearance of the reported hallucination.

Another prosecution expert, psychiatrist Dr. Avram Mack, concluded that Clancy had suffered from a major depressive episode but remained capable of distinguishing right from wrong. Prosecutors pointed to statements and conduct surrounding the deaths as evidence that she understood their meaning.

The competing testimony gave jurors two incompatible explanations. The defense experts saw psychosis where prosecution experts saw depression, dissociation and a person who retained criminal responsibility.

The Case Raises Questions About Postpartum Psychosis

Postpartum psychosis is rare but represents a psychiatric emergency. Estimates cited by experts place its incidence at about one or two cases for every 1,000 births. Symptoms can include delusions, hallucinations, severe mood disturbance, mania, confusion and loss of contact with reality.

The condition also presents complications for courts because a psychiatric diagnosis and legal insanity are separate concepts. A defendant can have a severe mental illness and remain criminally responsible. Conversely, the absence of an obvious history of hallucinations does not by itself establish that psychosis was impossible.

Clancy’s case added another dispute: timing. Callan was eight months old when the children died. Some prosecution testimony focused on narrower definitions of the postpartum period, while defense experts argued that postpartum psychiatric illness can emerge or continue beyond those boundaries.

The result was not a trial about whether postpartum psychosis exists. Both sides dealt with psychiatric disease. The dispute was whether Clancy had suffered from psychosis at the critical moment and, if she had, what effect it had on her capacity to understand or control her actions.

The Jury Is Asked to Decide Criminal Responsibility

After weeks of testimony, the case went to a jury of nine women and three men in late August.

The jurors faced a task that differed from the usual factual question in a murder trial. They did not need to determine who killed Cora, Dawson and Callan. Clancy had acknowledged doing so. They had to determine her criminal responsibility and consider the available homicide verdicts under the judge’s instructions.

The jury deliberated for days. By September 1, it reported that it was deadlocked. Judge Sullivan instructed the panel to continue its work. The deliberations stretched through the week, eventually exceeding 38 hours across seven days.

Then the dispute inside the jury room itself became part of the case.

A Dispute Over One Juror Pushes the Trial Toward Mistrial

The jury foreperson reported concerns involving one juror and the application of the reasonable-doubt standard. Reports from the proceedings indicated an 11-1 division, with the defense arguing that the lone juror was not applying the law as instructed.

Reddington asked Judge Sullivan to investigate and sought removal of the juror. The judge declined, concluding that the circumstances did not establish grounds to remove a deliberating juror. The defense maintained that the issue involved more than disagreement over the evidence and concerned whether the juror was following the court’s legal instructions.

Clancy’s lawyers then sought emergency intervention from the Massachusetts Supreme Judicial Court. The effort failed. With no judicial basis to alter the jury and no indication that further deliberations would produce unanimity, the trial reached its end.

On September 4, 2026, Judge Sullivan declared a mistrial.

The Mistrial Leaves Lindsay Clancy Without a Verdict

The mistrial did not establish that Clancy was guilty. It did not establish that she was not criminally responsible. It did not amount to an acquittal.

Instead, the first trial ended without a legal resolution because the jury could not return the unanimous verdict required in a Massachusetts criminal case. Clancy remains charged in the deaths of all three children.

She remains in psychiatric care at Tewksbury State Hospital while the case continues. A status hearing is scheduled for September 29, 2026, when the parties are expected to address the path forward.

Prosecutors can seek another trial. A negotiated resolution is another possibility. Legal experts have also noted that the Commonwealth can reassess its case after learning where the first jury divided and which evidence jurors found persuasive. Dismissal remains possible as a legal matter, but there was no indication when the mistrial was declared that prosecutors intended to abandon the prosecution.

Civil Lawsuits Raise a Separate Question About Clancy’s Treatment

The criminal prosecution is not the only litigation stemming from the deaths.

Lindsay Clancy and Patrick Clancy have pursued separate civil actions against medical providers involved in her psychiatric treatment. The claims allege failures in diagnosing and treating her condition before January 24, including allegations concerning medication management and the failure to recognize bipolar disorder and postpartum psychosis. Those allegations remain separate from the criminal case and require their own proof.

The civil cases could also be affected by what happens next in the prosecution. A second criminal trial would keep questions surrounding Clancy’s statements, medical history and Fifth Amendment rights alive, which could complicate or delay related civil proceedings.

Those lawsuits extend the central question beyond Clancy’s criminal responsibility. They ask whether the medical system that treated her recognized the danger in time and whether different treatment could have prevented the deaths.

Three Children Remain at the Center of the Case

The psychiatric and legal complexity of Commonwealth v. Lindsay Clancy can obscure the simplest fact underlying the proceedings: three children died.

Cora was five. Dawson was three. Callan was eight months old. Their father went out to collect medication and dinner on January 24, 2023, and returned to a home in which his three children had been attacked and his wife had attempted suicide.

The criminal trial was required to examine Clancy’s mental condition because Massachusetts law makes criminal responsibility a central question when the defense is raised. The jury’s inability to answer that question does not resolve the competing medical theories, nor does it change what happened to the children.

It does explain why the case has proved so difficult. The jury was not choosing between a theory in which Clancy was mentally ill and one in which she was healthy. It was asked to decide the legal consequences of mental illness in a case involving conduct that was undisputed and devastating.

20/20 Revisits the Case Hours After the Trial Collapses

ABC’s 20/20: “The Trial of Lindsay Clancy” enters the story at a pivotal point. The September 4 special examines the children’s deaths, Clancy’s mental-health history, the competing prosecution and defense cases and the expert evidence that left the jury divided.

The mistrial also means the 20/20 special cannot provide the conventional ending of a true-crime trial report. More than three and a half years after Cora, Dawson and Callan died, the criminal case has produced no final verdict. Clancy remains accused of their murders, while the defense continues to maintain that postpartum psychosis made her not criminally responsible.

What happens next will determine whether another jury is asked to confront the same question. For now, the first trial has ended where the debate surrounding the case began: with agreement about what Lindsay Clancy did, but a profound disagreement over her state of mind when she did it.

“The Trial of Lindsay Clancy – Special Edition of 20/20” airs Friday, September 4, 2026, from 9:00-10:00 p.m. EDT on ABC and streams the following day on Disney+ and Hulu.