(CNN) — Opening statements are set to begin Monday in the triple-murder trial of Lindsay Clancy, the Massachusetts mother who has argued she is not criminally responsible for fatally strangling her three young children.
Clancy, a 35-year-old former labor and delivery nurse at a hospital in Boston, has pleaded not guilty to three counts of murder for the killings of her children Cora, 5; Dawson, 3; and 8-month-old Callan.
The opening statements mark the start of Clancy’s trial in a case that will explore the controversial “insanity defense” and the severity of postpartum mental illness.
The core facts of the killings are not in dispute: On January 24, 2023, Clancy fatally strangled her three children in the basement of their Duxbury home using exercise resistance bands. She then cut her wrists and neck and jumped from a second-story window in a suicide attempt, leaving her partially paralyzed.
Instead, the key issue is her culpability.
Prosecutors say Clancy showed “deliberate premeditation, extreme atrocity or cruelty, and the state of mind of the defendant.” However, her attorney argues she was suffering from postpartum psychosis and extreme mental illness, so she was not responsible for her actions.
In a civil lawsuit against her medical providers, Clancy said a voice in her head ordered her to kill the children and herself.
“I lost all control. My body started acting without any control on my part,” Clancy said in the lawsuit. “I was just following commands, ‘all action.’ This voice demanded action.”
The testimony is expected to focus heavily on dueling psychiatric and medical experts testifying about postpartum mental illness. The trial could last six to eight weeks. She faces life in prison if convicted. She is being held at the public Tewksbury Hospital in Massachusetts.
The key witness in the case could be her husband Patrick Clancy, who went out to pick up takeout food that January 2023 day and came home to find the gruesome scene. He has indicated he shares his wife’s perspective on her mental illness.
“I wasn’t married to a monster—I was married to someone who got sick,” he told The New Yorker in a 2024 interview.
Clancy’s mental health struggles
In Lindsay Clancy’s lawsuit against her medical providers, she wrote about her deteriorating anxiety, depression, insomnia, auditory hallucinations and suicidal thoughts after the birth of her third child.
She saw a series of doctors and was prescribed about a dozen different drugs – antidepressants, sedatives, benzodiazepines and antipsychotics – from October 2022 leading up to the January 2023 killings, according to the lawsuit. She twice checked herself into a hospital for psychiatric care, but her problems worsened, the lawsuit states.
“This is a situation that clearly was a product of mental illness,” her attorney Kevin Reddington said at a 2023 arraignment hearing.
After her arrest, Clancy was ultimately diagnosed with postpartum severe bipolar disorder, the lawsuit states. The suit argues the medical providers who oversaw her treatment failed to properly diagnose her and exacerbated her problems with a “disorganized, uncoordinated” course of medications.
“Lindsay now faces a lifetime of physical disability, psychological trauma, and the unbearable grief of waking up every day knowing she killed her children – all of which could have been prevented had Defendants provided competent medical care,” her lawsuit states.
All the providers declined to speak with CNN about ongoing litigation.
Legal experts told CNN the insanity defense is a difficult argument to make successfully.
“I think there’s an ongoing kind of perception that insanity pleas are kind of a get-out-of-jail-free card that attorneys throw on the table,” said Joni Johnston, an investigator and forensic psychiatrist who conducts psychological evaluations of criminal offenders. “It’s a pretty rare defense to use – and an even rarer one to be successful.”
If jurors find Clancy cannot be held criminally responsible for the deaths of her children, the court would likely begin the legal process to have her committed to a state psychiatric hospital.
Broadly, Clancy’s case is similar to the infamous trial of Andrea Yates, the Texas mother who drowned her five children in their bathtub in 2001. She pleaded not guilty by reason of insanity, and after an initial murder conviction was overturned on appeal, a jury sided with her in a 2006 retrial. She remains institutionalized at a state hospital.
Perhaps the most well-known use of the insanity defense was in the trial of John Hinckley Jr., the man who shot President Ronald Reagan and three others in 1981 in what he said was an attempt to impress the actress Jodie Foster. The jury found him not guilty by reason of insanity. Hinckley spent nearly 30 years at a mental hospital before his release in 2016.
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