Aug. 21 (UPI) — Defense lawyers representing Massachusetts mother Lindsay Clancy, on trial for the murders of her three children, rested their case Friday after testimony from a doctor who claimed she is innocent due to mental illness.

Attorney Kevin Reddington told the presiding judge in Plymouth, Mass., Superior Court that the defense had concluded its case following the testimony of Dr. Phillip Resnick, a forensic psychiatrist with expertise in postpartum disorders.

He told jurors Clancy was “frankly psychotic” on Jan. 24, 2023, when she killed her children.

A series of defense witnesses this week sought to show Clancy, 36, is not guilty of murdering her children — 5-year-old Cora, 3-year-old Dawson and 8-month-old Callan — at their Duxbury, Mass., home.

Clancy cut herself and jumped from a second-story window in a failed suicide attempt following the slayings, after which she became paralyzed from the waist down.

While not denying she killed the children by strangulation, they contend she is not criminally responsible because she was suffering from bipolar disorder and postpartum psychosis.

She faces a possible sentence of mandatory life imprisonment without the chance of parole.

When questioned by Reddington, Resnick stated in his video testimony that based on his diagnosis Clancy suffered from a “postpartum psychosis” following the birth of Callum, noting that she heard voices commanding her kill her children and herself.

This, he said, triggered a “delusion of influence” in which a victim feels their body is overtaken by an “external force,” and thus Clancy should not be held criminally responsible for her actions, the Boston Globe reported.

“She felt that she had to obey the instructions,” he said. “It was a matter where she was just following the command, rather than being able to make any decision to do this or not.”

After the defense rested, prosecutors called several rebuttal witnesses including Dr. Avram Mack, a psychiatrist, who agreed with prosecutors that Clancy was able to understand that her actions were wrong when she killed her children, thus making her guilty of murder under state law.

He testified that Clancy had interacted normally with other people in the hours before the killings.

“There was the ability to act normally,” he said, adding that Clancy had said “Go to God” while committing the slayings, which he took to mean she knew her children were innocent as they died.