When her trial is set to begin, on Monday, her lawyer will try to persuade a jury to acquit her of those charges due to “lack of criminal responsibility,” arguing that she was unable to resist a voice in her head telling her to kill her children and herself.
Jury selection is slated to take place in Plymouth Superior Court in a trial that is expected to last six to eight weeks and feature dueling mental health experts, graphic evidence, and emotional testimony from Clancy’s then-husband, Patrick, who discovered their childrens’ lifeless bodies.
Judge William F. Sullivan plans to seat 18 jurors, including six alternates. The prosecution lists 168 potential witnesses in a court filing, while the defense lists 53.
If convicted of first-degree murder, Clancy, now 35, will face a mandatory sentence of life in prison without parole. If found not guilty due to lack of criminal responsibility, more commonly known as insanity, she will be committed to a state psychiatric hospital, where she will be evaluated periodically and could be released some day if authorities conclude she would not pose a threat to the community.
The former Massachusetts General Hospital nurse is paralyzed from the waist down and remains in custody without bail at Tewksbury Hospital, where she receives treatment.
Cases like Clancy’s, of mothers killing their children due to purported mental illness, are rare in Massachusetts and difficult for defendants to win with an insanity defense, according to criminal defense attorneys who have represented mentally ill clients.
The challenge is showing jurors that Clancy’s mental illness prevented her from controlling her actions or realizing the wrongfulness of them.
“A big part of this case is going to be to try to educate jurors about postpartum depression and how severe it can be,” said Boston attorney Keith Halpern, who has handled about 10 murder cases involving an insanity defense, but has no involvement in Clancy’s case. “Not everyone who develops postpartum depression becomes psychotic and not everyone who becomes psychotic becomes violent.”
But some do.
The challenge for the defense is to find jurors “who can step back from the horror of what happened and fairly evaluate the defendant’s mental state,” said Boston attorney William Fick. “I think it’s difficult for people to say that someone is not responsible for a horrific crime.”
Plymouth District Attorney Timothy Cruz alleges that Clancy plotted the murders and “did not feel love or connection with some of her kids,” according to court filings.
During previous court proceedings, Assistant District Attorney Jennifer Sprague alleged that four days before the slayings, Clancy conducted an Internet search on her cellphone for the phrase, “can you treat a sociopath.”
She alleged that Clancy conducted research about how to kill, then strangled her children with exercise bands on Jan. 24, 2023, after sending Patrick to pick up takeout dinner for the family.
Clancy’s attorney, Kevin Reddington, has described her as a loving mother who desperately sought help for postpartum depression and anxiety in the months after the birth of her third child and was overmedicated on 13 drugs, leading to “homicidal ideation, suicidal ideation.”
The judge has ruled that prosecutors may play a recording for jurors of Patrick Clancy’s anguished 911 call after finding his injured wife outside their home, then discovering their children’s bodies in the basement and screaming, “She killed the kids!”
Patrick, who now lives in New York and is on both the prosecution and defense witness lists, has remarried since his divorce from Lindsay, according to Reddington. Shortly after the slayings, Patrick urged the public to forgive Lindsay. In a 2024 article published by The New Yorker, he said, “I wasn’t married to a monster — I was married to someone who got sick.“
At the prosecution’s request, Sullivan ordered The New Yorker to turn over documents related to statements Lindsay Clancy made to her husband and other people interviewed for the story “regarding her actions or state of mind” leading up to the slayings.
Reddington has said he’ll present evidence at trial of Clancy’s frantic efforts to get help as she struggled with postpartum mental illness.
Earlier this year, Lindsay and Patrick Clancy filed separate lawsuits against a psychiatrist and other medical providers they allege failed to properly diagnose or treat her severe postpartum psychiatric condition. She was voluntarily committed to McLean Hospital for treatment just weeks before the slayings.
Lindsay Clancy’s suit says that on the day of the slayings she experienced “command auditory hallucinations,” as a male voice instructed her to kill her children and herself and said it was her “last chance” to do it.
“I lost all control. My body started acting without any control on my part,” the complaint quotes Clancy as saying. “I was just following commands, ‘all action.’ This voice demanded action.”
As Clancy strangled her children, according to the lawsuit, she told them, “Go to God, baby.”
Boston criminal defense attorney Robert Sheketoff, who is not involved but has watched the case unfold, said, “A mother killing her kids is such unusual behavior that it screams out to me she has an unusual mental health problem and is not a premeditated murderer.”
Yet, he said, the odds are against an acquittal because “she killed three kids” and if jurors “want to blame someone, she’s the one you can blame.”
It’s not unusual for defense and prosecution experts to agree that a defendant is mentally ill, yet disagree over whether she was capable of controlling her behavior, according to Sheketoff.
He speculated that Clancy’s case may largely hinge on “who the jury finds more credible, the defense expert or the prosecution expert.”
Under state law, the burden is on prosecutors to prove beyond a reasonable doubt that Clancy was not mentally ill when she killed her children, or, if she was, she knew it was wrong or illegal and was capable of obeying the law.
“In many instances the inability to conform one’s behavior to the law is caused by a delusion or a psychosis where the defendant at the time of the crime is perceiving a distorted reality,” said Salem attorney Denise Regan, who has handled a number of insanity cases. “They actually believe what they are doing is something that has to be done, that it is the right thing.”
Regan said it’s important for jurors to know that Clancy will not “just be released to the streets” if they find her not guilty because of mental illness.
Based on a decades-old ruling by the Massachusetts Supreme Judicial Court, jurors are instructed that a defendant found not guilty of murder due to mental illness will be committed to a psychiatric hospital.
A quarter century after Andrea Yates drowned her five children in Texas while suffering from postpartum mental illness — in one of the most notorious such cases in recent time — she remains in a psychiatric hospital. Every year, she waives her right to an evaluation to determine whether she should be released, according to her attorney.
George Parnham, a Houston attorney who represented Yates, said the challenge for Clancy’s defense is “to have the jury look through the eyes of the woman who basically did what she did for reasons that were probably psychotic in nature, but real to her.”
Yates believed she was “doing the right thing” by drowning her children in 2001 so they would go to heaven, her defense argued. A Texas jury convicted her of capital murder, but after that verdict was overturned, a second jury found Yates not guilty by reason of insanity.
“You have to get the jury to see the actions that occurred through the eyes of the woman who gave life to those children,” Parnham said. “That’s the very essence of insanity. How in the world does a mother take the life of a child who she gave life to? How does it happen?”
Shelley Murphy can be reached at shelley.murphy@globe.com. Follow her @shelleymurph.