Lindsay Clancy judge declares a mistrial after the state’s top court denies defense’s appeal

Lindsay Clancy's triple-murder trial ended in a mistrial Friday, following a last-minute appeal by her attorney to prevent the outcome after the jury failed to reach a unanimous verdict.

The jury weighing Clancy's fate was sent back twice to deliberate but said that "with a heavy heart" it was ultimately unable to reach a verdict after seven days of deliberations.

With the deadlock, Judge William Sullivan told the court he would declare a mistrial in the case, prompting Clancy's defense attorney, Kevin Reddington, to announce his intent to appeal to Massachusetts' top court, an effort which ultimately failed.

The jury was tasked with determining whether Clancy, 36, was criminally responsible in the 2023 deaths of her three young children — Cora, 5, Dawson, 3, and Callan, 8 months — or whether she was not guilty by reason of lack of criminal responsibility because of mental illness.

Sullivan gave Reddington an hour for his appeal Friday morning. The hour stretched into two before Reddington's associate, Dana Goldblatt, was able to ask a state Supreme Judicial Court judge on a Zoom call to remove a holdout juror from the panel.

Goldblatt argued that they believe this juror is refusing to "follow what the law states." But Supreme Judicial Court Associate Justice Dalila Argaez Wendlandt denied the stay.

Plymouth County District Attorney Timothy Cruz will now decide whether to try Clancy again in front of a different jury, for first-degree murder or less serious charges.

Clancy had pleaded not guilty to three first-degree murder charges.

Before dismissing the jury, Sullivan thanked them for their dedication throughout the nearly six-week trial.

"You knew how difficult the case was going to be to listen to, facts-wise, but still you braced for that duty," he said.

He also later acknowledged the work of the attorneys who took part in the trial on the contentious case.

"I wanted to compliment all three counsel," Sullivan said. "A trial like this is so hard, so difficult, and so I just kind of wanted to to thank the three of you for your efforts in regards to this."

Reddington asserted he wanted to get back into the courtroom as soon as possible to argue next steps, but a status conference has been set for Sept. 29.

Jury deliberations

Sullivan got the first deadlock note Tuesday , the fourth day of deliberations, and dismissed the jurors after asking them to continue to work toward a verdict.

On Wednesday, the jury issued a second note saying it is "still unable to come to a unanimous decision."

Sullivan, at that point, read the jurors what's known as Tuey-Rodriguez instructions, which essentially asks them to give deliberations one last chance and tells them that it's "desirable" they reach a verdict.

Under Massachusetts law, a judge can only ask a jury to keep deliberating twice, unless it consents to further deliberations. If the jury still cannot reach a unanimous verdict after the third deadlock, the judge can declare a mistrial, which Sullivan did.

The defense's argument

Clancy's defense argued she was not criminally responsible for the Jan. 24, 2023, killings because she was mentally ill with postpartum psychosis , a rare condition that can alter a new mother's sense of reality and is considered a psychiatric emergency. It is more severe and less common than postpartum depression.

Her attorneys argued that she had mentally deteriorated over the preceding months and, despite repeated efforts to seek psychiatric help including calling the suicide hotline , she was never properly diagnosed. Instead, she was given a spate of different medications over a matter of months to treat her symptoms or the adverse reactions to some of the medications.

In closing arguments, Reddington blamed "the damn medicine and the lousy medical care that she got" for the trajectory from happy family to the murders.

He claimed the prosecution was trying to manipulate the jury by portraying Clancy as control-obsessed and for downplaying the severity of her suicide attempt, which left her paralyzed from the waist down.

He doubled down on Clancy's claim that she heard a male voice compelling her to kill her kids — a point the prosecution has tried to pick apart in trial. She told a hospital chaplain about the voice, and told her then-husband over the phone in a call heard by a forensic psychologist.

He also emphasized the testimony of forensic psychiatrist Dr. Phillip Resnick who concluded that Clancy was psychotic at the time of the murders.

"This young lady is not guilty of the killing of her children because she was suffering from a disease and defect," Reddington said.

The prosecution's argument

Prosecutors argued Clancy was in full control of her faculties at the time of the killings and deliberately planned the murders. They acknowledged that she was struggling with her mental health, but claimed she manipulated her doctors and treatment and argued that she was not in psychosis at the time of the killings.

They argued she intentionally sent her then-husband, Patrick Clancy, out to pick up dinner and go to a CVS store the evening of the murders. They said she looked up how long the trip would take and called the store to make sure it had a medication in stock to buy herself enough time.

Then, Clancy methodically killed the kids one after another and then attempted suicide by throwing herself out of her second-story bedroom window, prosecutors said.

Patrick Clancy testified that he returned home that evening to find "blood everywhere."

Clancy was bleeding on the ground outside their home, he said. The children were in the basement, unresponsive and with exercise bands around their necks.

While the trial has seen Clancy emerge as a symbol of the problems plaguing maternal healthcare, in her closing arguments, Plymouth County Assistant District Attorney Jennifer Sprague told the jury this trial wasn't about the mental health system or how it treats women.

Sprague conceded Clancy had mental health issues and was depressed. But, she said, it wasn't the fault of the providers that Clancy wasn't getting better.

In the months leading up to the killings, Clancy told family members she was getting better but told psychiatrist, Dr. Jennifer Tufts, that she was depressed, Sprague said.

But she didn't tell Tufts the whole story either, Sprague said.

During her sessions with Tufts, Clancy "denied having a suicide plan, denied wanting to hurt anyone else, denied voices" and "showed no signs of psychosis."

Sprague walked the jury through the killings, detailing how Clancy used the exercise bands to strangle her children, calling it as "extreme atrocity and cruelty."

"Those kids were her protective factor," Sprague said. "Those kids were keeping her from ending her misery. And so she had to remove the protective factor. … It was a choice."

The livestreamed trial captivated the nation and prompted an outcry of support for Clancy, with hundreds gathering outside of the courtroom in solidarity. It also spawned conspiracy theories and chatter on social media by armchair crime junkies.

If you or someone you know is struggling or in emotional distress, call or text 988, or chat at 988lifeline.org 24/7, to reach the 988 Suicide & Crisis Lifeline. For additional resources, visit SpeakingOfSuicide.com/resources .

This article was originally published on NBCNews.com