The trial of Lindsay Clancy was covered as a postpartum-psychosis story. That is the defence frame. The Plymouth County District Attorney's medical theory got less airtime: not "she was fine," and not "she is a monster with no illness," but a specific forensic claim that Massachusetts law actually requires the state to meet.
She strangled Cora, 5, Dawson, 3, and eight-month-old Callan in the family's Duxbury basement on January 24, 2023, then jumped from a second-story window. She does not deny the acts. The question at Plymouth Superior Court was criminal responsibility under Commonwealth v. McHoul: did she, at the time, lack substantial capacity to appreciate the wrongfulness of what she was doing or to conform her conduct to the law? The jury hung after seven days, reportedly 11–1 for lack of responsibility. District Attorney Timothy Cruz still described "the cruel and calculated killing of three innocents" and said the investigation did not establish that postpartum depression caused the homicides. That is the theory worth laying out in full, because it is the part most coverage treated as a footnote.
Prosecutors Jennifer Sprague and Shanan Buckingham conceded mental illness and a genuine suicide attempt. They rejected the package the defence needed: bipolar disorder plus acute postpartum psychosis with a command hallucination that stripped her of control.
Their treating-clinician file was the first half of that case. In the months after Callan's birth, Clancy saw psychiatrist Dr. Jennifer Tufts and psychiatric nurse practitioner Rebecca Jollotta. The working diagnoses in that period were anxiety, adjustment disorder with depressed mood, and later major depression without psychotic features, not psychosis. She denied hearing voices that told her to hurt herself or others. She reported insomnia, numbness, forced bonding with the baby, fear that medication was making her worse, and intrusive dark thoughts. She sought a hotline, an ER, a partial-hospital program that did not take her, and a short stay at McLean. Dr. Alia Goodheart, who saw her at McLean weeks before the killings, recorded major depressive disorder, severe, without psychotic features. Two weeks before the deaths she was in a psychiatric hospital and, on the state's telling, did not report hallucinations there.
That timeline matters to the DA for a simple reason. Postpartum psychosis, when it is present, is usually florid enough that someone documents it: disorganisation, delusion, or hallucination before the homicidal hour. The state's clinicians said they did not see that picture. The first explicit "postpartum psychosis" language in a hospital chart that jurors heard came after the children were dead, in a Brigham and Women's note written when she was already critically injured.
The prosecution's point was not that a chart is omniscient. It was that the defence diagnosis was built backward from the crime.
Once treating records were in, the DA put on forensic examiners to give the depression a motive structure. Dr. Avram Mack, a forensic psychiatrist retained through Park Dietz and Associates, interviewed Clancy at Tewksbury Hospital on April 10 and 12, 2026, and reviewed thousands of pages. He testified to a major depressive episode and to retained capacity: she knew right from wrong and could control her conduct. He did not find psychosis at the time of the killings. Cross-examination went after how much he knew about postpartum psychosis. The state's answer was that the legal question is capacity, not whether the witness can lecture on perinatal psychiatry.
Dr. Kirk Heilbrun, a forensic psychologist, spent about ten and a half hours with her over three days in April 2026, some of it with Mack present, a design critics later said compromised independence. Heilbrun's formulation is the one John Leake isolates in the Focal Points essay: suicide fused with "altruistic filicide," "killing your kids out of love." She had carried intrusive suicidal thoughts for months. The children, in this telling, were not the target of hatred. They were the reason she could not complete a suicide. Sprague's closing made that concrete: they were her "protective factors." To end her misery she had to remove them, and she expected no earthly consequence because she planned to die with them.
Heilbrun also drew a time box around the voice. He said she reported a hallucination only for the roughly eighteen minutes it took to kill the children, not as a weeks-long psychotic process. If that is true, the command-hallucination story is a spike, not a syndrome. If it is false, the state's own expert has undercounted the illness. Either way, that eighteen-minute claim is the sharpest medical disagreement in the file, and it barely survived in general-audience pieces.
A third prosecution voice, Dr. Gregory Saathoff, evaluated her twice by Zoom. He rejected postpartum psychosis and described anxiety and bipolar illness triggered by severe insomnia he tied to sertraline (Zoloft). That is a different medical story again: not "only sad," not "command psychosis," but a sleep-and-medication spiral that still, in his view, left her responsible.
The DA did not need a novel motive. Motive is not an element. They offered one so a juror who accepted depression would still have a non-psychotic path to guilt.
The planning evidence is what they used as a proxy for intact executive function. She sent her husband out for takeout and medication and checked how long he would be gone. There was testimony about looking up how far the restaurant and pharmacy were from the house. Then the acts themselves: three children, in sequence, with exercise bands, in the basement. The state's inference is ugly and legally ordinary. A person in the grip of a command hallucination can still perform a sequence. A person who can wait for the house to empty, time an errand, and complete three killings is, on the Commonwealth's reading, still choosing. Buckingham told jurors she "acted intentionally, rationally and swiftly." Cruz, after the mistrial, said she was in control of her actions.
That is why "altruistic filicide" is doing work. The literature on mothers who kill children and then try to die often describes a depressed, not frankly psychotic, actor who believes the children cannot survive her death or will be better off dead than motherless. Leake notes the category is real and the evidence in any one case is usually thin. The DA imported the category so "she loved them" would not automatically mean "she was insane." Defence expert Dr. Phillip Resnick, who knows that same literature, used the love-and-welfare preoccupation as a mark of psychosis and altruistic filicide inside a psychotic break. Same vocabulary, opposite legal landing.
The defence medical case was heavier in public narrative: Dr. Paul Zeizel's many early interviews and reconstruction; Resnick on severe postpartum psychosis and a command hallucination; Dr. Donald Condie on psychopharmacology without a personal exam, arguing providers stacked drugs instead of testing or revising the diagnosis; some thirty prescriptions across thirteen drugs in four months, including Zoloft, Prozac, Seroquel, Klonopin, Ativan, Remeron. Antidepressants in a possible bipolar or psychotic postpartum patient is a known clinical hazard. That is a strong systems indictment. It is not, by itself, an answer to McHoul.
The prosecution's reply to the drug story was narrow. Treating doctors said she denied psychosis when asked. They saw worsening mood and sleep, not a documented break with reality. Some of the same medicines the defence calls iatrogenic are, in Saathoff's version, the cause of the insomnia that unmasked bipolar anxiety, still short of the defence's legal destination.
Postpartum psychosis is rare, treatable, and easy to explain as a medical tragedy. "Extended suicide" sounds like a prosecutor's moralism. It is actually a clinical phrase, and it is the only way the state could admit she was crushed and still ask for first-degree murder: deliberate premeditation or extreme atrocity. The media preferred the rare-disease frame. The DA preferred the chart, the errand, and two late forensic exams that found depression with a plan.
A hung jury, especially 11–1 the other way, is a verdict on persuasiveness, not on whether the theory was ever stated. Cruz has not announced a retrial. If there is one, the medical fight will be the same: whether a major depressive episode plus a timed absence plus a claimed eighteen-minute voice is psychosis that destroys responsibility, or depression that organises a murder-suicide and fails only at the suicide.
That is the Plymouth theory. It is colder than the headline illness. It is also the one the Commonwealth actually tried to prove, but failed in a woke feminist Democrat culture, of #BelieveAllWomen.
https://www.thefocalpoints.com/p/is-the-plymouth-das-theory-of-lindsay