The Lindsay Clancy Mistrial: Understanding hung juries and reasonable doubt

By: Julianna Gentile

Content Warning: This paper contains discussion of mental illness, suicide, violence, and the deaths of children, including descriptions of murder and criminal proceedings that some readers may find distressing.

Background

The Lindsay Clancy murder trial is one of the most watched court cases of the year, and the case only received more attention due to its controversial end. Clancy, a former labor and delivery nurse, was charged with three counts of murder following the deaths of her three children in January of 2023. The children were found dead at the family’s home in Duxbury, Massachusetts, after being strangled with exercise bands. Lindsay was found paralyzed from the waist down outside the home after attempting to commit suicide by cutting her wrists and throat and jumping out of a second-story window following the murders. Clancy had reportedly been seeking care for severe postpartum depression in the months after the birth of her youngest child, Callan, who was just 8 months old. The central question at trial was not whether Clancy had caused her children’s deaths, but whether she could be held criminally responsible for doing so. Her defense argued that she was suffering from postpartum psychosis and was therefore not criminally responsible for her actions. Prosecutors challenged that account, arguing that Clancy understood what she was doing and acted deliberately.

Already a highly publicized story, the trial received even more attention when it was declared a mistrial on September 4, 2026, after seven days of jury deliberations. The jury was reportedly split 11–1 in favor of finding Clancy not guilty by reason of insanity, with one holdout juror preventing the unanimous verdict required in the case.

Hung Juries and Jury Unanimity

In situations like the Clancy case wherein one or more jurors prevent a verdict from being reached, it is called a deadlocked, or hung jury. When a hung jury occurs, the judge declares a mistrial, and the prosecution team decides whether or not they want to retry the case.

Juries are required to reach a unanimous verdict in any state or federal criminal trial where the defendant is accused of a non-petty offense. This applies to any case where the maximum prison sentence exceeds six months. While federal criminal trials have required jury unanimity under the Sixth Amendment since at least the late 1800s, state criminal trials were only required to follow this rule in 2020 following its incorporation under the Fourteenth Amendment. 

The unanimity requirement means that an 11-1 vote carries no more legal ability to produce a verdict than a more evenly divided jury. Even if eleven jurors agree, the court cannot enter a verdict unless all twelve deliberating jurors agree. The requirement is intended to ensure that each juror individually concludes that the prosecution has satisfied its burden rather than simply accepting the majority’s view.

In cases with deadlocked juries, there are some instances when a holdout juror can be removed. Massachusetts law allows a deliberating juror to be removed only in cases of an established emergency or another compelling reason. Kevin Reddington, Clancy’s defense lawyer, attempted to have the holdout juror removed from the jury following a note from the juror foreperson claiming that “the [lone] juror was not following the court’s reasonable-doubt instruction.” Judge William Sullivan questioned the jurors, repeated his instructions on reasonable doubt, and allowed deliberations to continue without removal of the lone juror. As the deadlock continued, Sullivan also gave the jury a Tuey-Rodriquez instruction, which encouraged the jurors to reconsider the case and one another’s opinions while reminding them not to abandon honestly held beliefs simply to reach a unanimous verdict.

Reasonable Doubt

Reasonable doubt is the legal burden of proof required for a criminal conviction. The prosecution has to prove through evidence and testimony that the defendant is guilty beyond a reasonable doubt to get a conviction. In terms of the Clancy case, the prosecution team was trying to convince the jury that Lindsay Clancy murdered her children and was legally responsible for her actions despite her mental illness, which they were not successful in doing. 

Having a mental illness by itself does not automatically make someone not legally responsible. The question is whether a mental illness substantially impaired the person's ability to comprehend the wrongfulness of their actions or to conform their behavior to the requirements of the law. This distinction meant that the jury could believe Clancy suffered from severe mental illness while still disagreeing over whether that illness satisfied Massachusetts's legal standard for lack of criminal responsibility.

The holdout juror in the case was accused by other members of the jury of failing to follow the court's instructions regarding reasonable doubt. Allegedly, the juror claimed that he “had reasonable doubt,” but that he would not “say that she’s not guilty by reason of insanity.” That allegation became significant because, under Massachusetts law, the Commonwealth bore the burden of proving Clancy's criminal responsibility beyond a reasonable doubt. At the same time, disagreement with the other eleven jurors would not by itself establish that the holdout was disregarding the law, creating a difficult distinction between a juror refusing to follow instructions and a juror independently interpreting the evidence. 

Conclusion

A mistrial does not mean that Clancy will walk free. Prosecutors are now able to decide if they will retry Clancy with a new jury, or if they will attempt to reach a deal with the defense team. Likewise, a verdict finding Clancy not guilty by reason of lack of criminal responsibility would not have meant that she would be released. Massachusetts law provides procedures for psychiatric evaluation and possible civil commitment following such an acquittal. For now, however, the mistrial leaves the criminal case unresolved. Prosecutors may pursue another trial, negotiate a resolution with the defense, or otherwise determine how to proceed with the charges. A retrial following a genuinely deadlocked jury generally does not violate the constitutional protection against double jeopardy because the first jury never reached a final verdict.

Works Cited

Braccia, Marian. “One Juror, No Verdict: What the Lindsay Clancy Mistrial Tells Us About Jury Unanimity.” Voices at Temple, September 9, 2026. https://www2.law.temple.edu/voices/lindsay-clancy-mistrial-jury-unanimity/.

Decker & Jones. “Christopher R. Decker Provides Live Analysis as Lindsay Clancy Trial Ends in Mistrial.” September 4, 2026. https://deckerjoneslaw.com/news/christopher-decker-lindsay-clancy-mistrial-legal-analysis/.

Derr, Greg. Lindsay Clancy and Attorney Kevin Reddington, Plymouth, Massachusetts, September 2, 2026. Photograph. Reuters, September 2, 2026. https://www.reuters.com/live/live-lindsay-clancy-returns-court-after-murder-case-mistrial-2026-09-29/.

Library of Congress. “Unanimity of the Jury.” Constitution Annotated. Accessed October 5, 2026. https://constitution.congress.gov/browse/essay/amdt6-4-4-3/ALDE_00013134/.

Serpa, Joe. “The Lindsay Clancy Jury Dispute: When Massachusetts Law Permits Removal of a Deliberating Juror.” Boston Criminal Defense Lawyer Blog, September 3, 2026. https://www.serpalaw.com/boston-criminal-law-updates/lindsay-clancy-juror-removal-massachusetts-law/.

Tabashneck, Stephanie. “Law and Severe Mental Illness: The Lindsay Clancy Trial.” Petrie-Flom Center, Harvard Law School. October 8, 2026. https://petrieflom.law.harvard.edu/2026/10/08/law-and-severe-mental-illness-the-lindsay-clancy-trial/.

Walsh, Aoife. “Holdout Juror in Clancy Case Admitted ‘Reasonable Doubt,’ Foreperson Says.” The Daily Record, September 9, 2026. https://thedailyrecord.com/2026/09/09/holdout-juror-massachusetts-clancy-case-admitted-reasonable-doubt/.