The defense blamed one juror for the deadlock.
The murder trial of Lindsay Clancy, the Massachusetts mom who killed her three young children while in the family's home on Jan. 24, 2023, ended Friday in a mistrial after seven days of juror deadlock.
Clancy's defense attorney, Kevin Reddington, claimed throughout that trial that she was suffering from postpartum psychosis when she strangled her children and attempted to take her own life. The prosecutors, Jennifer Sprague and Shanan Buckingham, argued that Clancy -- who pleaded not guilty to three counts of first-degree murder -- is criminally responsible for her children's deaths.
Judge William Sullivan, who oversaw the trial, set a court date of Sept. 29, 2026, to reconvene and determine next steps.
See below how the final days of the trial unfolded.
Watch a special edition of "20/20," "The Trial of Lindsay Clancy," airing Friday, Sept. 4, at 9/8c on ABC, streaming the next day on Disney+ and Hulu.
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Jurors have concluded a sixth day of deliberations with no verdict.
The judge said he would excuse them until 9 a.m. Friday and speak to them at that point.
The jury has deliberated for 36 hours so far.
As jurors filed out of the courtroom, Lindsay Clancy looked on.
Clancy's family left the courtroom carrying a box of letters her attorney Kevin Reddington said were messages of support from around the world.
In open court, defense attorney Kevin Reddington said there is one juror who is refusing to adhere to Judge William Sullivan's instructions. He has asked the judge to remove the juror who is refusing to listen.
"I don't feel it is proper for me to side with one side or the other in deliberations," Sullivan said.
It appears that is what Sullivan polled the jury about, whether they can adhere to the instructions.
Judge William Sullivan told the jury, "You are required to follow my instructions on the law as I gave them."
Sullivan reiterated his instruction about reasonable doubt.
He then returned jurors to their deliberations.
The judge is polling the jurors individually at sidebar.
Clancy is present while this occurs.
It was preceded by a disagreement between the two parties.
