A Massachusetts jury has declared itself deadlocked for the second consecutive day in the murder trial of Lindsay Clancy, a 36-year-old former obstetric nurse charged with killing her three young children in January 2023, prompting Judge William Sullivan to declare a mistrial. The jury of nine women and three men, after five days of deliberations spanning more than a week of a six-week trial, sent the judge a note stating: "After much deliberation, we are still unable to come to a unanimous decision." Sullivan had urged the panel to continue, issuing a formal last-ditch instruction — known in Massachusetts as a Tuey-Rodriguez charge — encouraging jurors to reconsider their positions while maintaining their individual conscience. The effort failed to break the impasse.

The facts of the case were never in dispute. Clancy strangled her three children — Cora, aged five, Dawson, three, and Callan, eight months — with elastic exercise bands in the basement of the family's home in Duxbury, a wealthy suburb south of Boston. She then cut herself and jumped from a second-floor window in an apparent suicide attempt, surviving but paralysed from the waist down. Her defence attorney argued that she was in the grip of severe postpartum psychosis at the time — a rare but serious psychiatric condition involving hallucinations and delusions — and could not distinguish right from wrong. He described her as a loving mother who heard a voice commanding her to kill her children and then herself. The prosecution, in contrast, maintained that Clancy acted with calculation and intent, pointing to evidence that she had sent her husband Patrick on errands shortly before the killings, and that she had appeared largely normal earlier that day, building a snowman with the children. More than 80 witnesses testified, including mental health experts on both sides, and over 300 pieces of documentary and physical evidence were submitted.

The trial had exposed deep divisions — mirrored in the jury room — over how to weigh Clancy's documented psychiatric history against the prosecution's evidence of deliberate planning. Court records showed she had been prescribed 13 different psychiatric medications in the four months before the killings and had twice called a suicide hotline. Some psychiatric experts who testified for the prosecution acknowledged she had shown signs of mental illness but argued she retained moral awareness at the moment of the killings. One expert noted it was "very unusual" that Clancy reported hearing a commanding voice for the first and only time during the act itself. The live-streamed trial drew national attention and sparked a broader public debate about postpartum mental health care in the United States; hundreds of supporters gathered outside the Plymouth courthouse wearing pink T-shirts reading "Peace for Lindsay," and a crowdfunding campaign by her parents raised more than one million dollars within days.

A mistrial — the result of a hung jury — does not constitute an acquittal. Clancy will remain in the psychiatric facility where she has been held throughout the proceedings, and prosecutors must now decide whether to retry the case with a new jury, negotiate a plea agreement, or drop the charges altogether. The possible verdicts that the jury had been weighing ranged from first-degree murder, which carries a mandatory sentence of life without parole in Massachusetts, through second-degree murder and manslaughter, to not guilty by reason of insanity — which would most likely result in detention in a secure psychiatric hospital. The case echoes that of Andrea Yates, the Texas mother who drowned her five children in 2001 and was eventually found not guilty by reason of insanity in a 2006 retrial after her first conviction was overturned. Both cases have forced American courts to grapple with a persistent and unresolved question: how the legal system should treat mothers whose severe mental illness leads to the deaths of their own children.