Medical Expert Weighs in on Lindsay Clancy Case and Postpartum Psychosis: 'Untethered from Reality'

"There is absolutely no doubt in my mind that postpartum psychosis can be the motivation for filicide," forensic psychiatrist Dr. Ian Lamoureux tells PEOPLE

Content warning: This article contains disturbing descriptions of violence.

A medical expert says the defense's claim that Lindsay Clancy, 32, may have suffered from postpartum psychosis during the alleged killings of her three kids has significant bearing in the Massachusetts mom's murder case.

"There is absolutely no doubt in my mind that postpartum psychosis can be the motivation for filicide," forensic psychiatrist Dr. Ian Lamoureux tells PEOPLE.

Clancy has been accused of strangling to death her children, 7-month-old Callan, 3-year-old son Dawson and 5-year-old Cora, in January.

She pleaded not guilty to two counts of murder, three counts of strangulation and three counts of assault and battery with a dangerous weapon.

However, prosecutors say Clancy killed her children with "deliberate premeditation and extreme atrocity and cruelty." During her arraignment on Feb. 7, it was revealed by the prosecution that Clancy used exercise bands to strangle Callan, Dawson and Cora. She then allegedly attempted suicide by cutting her wrists and neck and jumping out of a second-story window while her husband was away from their Duxbury, Mass., home picking up dinner for the family.

When he arrived back home, Patrick Clancy found his wife laying on the ground, seriously injured, in the backyard and called 911. Prosecutors say he eventually found their three kids unconscious in the basement.

Lindsay Clancy. Facebook

During Clancy's court hearing, her defense attorney, Kevin Reddington, argued, "This is not a situation that was planned by any means. This is a situation that clearly was a product of mental illness."

Reddington also stated that the effects of multiple medications doctors prescribed to treat Clancy's depression and anxiety, following the birth of her third child in 2022, including Prozac, Seroquel and Trazodone, were to blame for her "postpartum depression, as well as the possibility of postpartum psychosis."

Dr. Lamoureux, who has not formally reviewed Clancy's medical records, says while the diagnosis of postpartum psychosis — a condition where shortly after birth, a mother is effectively "untethered from reality" — appears to be accurate, he does not believe the overprescribing of medications to be the cause.

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"Typically, we do not see psychiatric medication, even when improperly prescribed and prescribed in excessive volume, to cause psychotic symptoms or homicidal thoughts," Lamoureux explains. "What it can do is cause a delirium, a medical state where you start to see psychotic symptoms occur."

"It may be the case that she had a pretty significant underlying condition, and what was seen was more a result of the condition itself with medications … being increased to try to catch up to the symptoms," he continued.

Lamoureux says Clancy's potential postpartum psychosis diagnosis is "not a moral failure. It's not an issue of character. It's an issue of mental illness."

Lindsay Clancy. Lindsay Marie Clancy Facebook

"They can be so depressed, they see life as so meaningless or so hopeless that they view it as a cruelty to allow their child to continue to exist in this world," he says.

"This is not something where the mother snaps," adds Lamoureux. "It's that this is typically a case where following birth, the mother is exhibiting increasingly worsening signs and symptoms of an illness, and then starts to really reach crescendo pitch of their illness, which culminates in the filicide."

Clancy, who doctors say is paralyzed from the waist down as a result of an alleged 20-foot leap from a second-story window, has been ordered to remain in her current hospital, until medically cleared to be transferred to a new facility.

A judge declined to set monetary bail due to her prognosis.

Clancy will next appear in court May 2.

If you or someone you know is considering suicide, please contact the 988 Suicide and Crisis Lifeline by dialing 988, text "STRENGTH" to the Crisis Text Line at 741741 or go to 988lifeline.org.