Experts failed to assess Clancy's thoughts during the killings, which are crucial for insanity.

Two prosecution experts interviewed Clancy together, compromising independent evaluations.

Defense expert saw Clancy soon after the killings but didn't directly link her delusions to the acts.

After an emotionally charged five-week trial, jurors were unable to unanimously decide whether Ms. Clancy murdered her three children with conscious premeditation or was legally insane. Judge William Sullivan declared a mistrial after the jury foreperson reported they were deadlocked.

The defense called two experts and the prosecution three rebuttal experts. Forensic psychologist Dr. Paul Zeizel was the first defense witness. His evaluation began only 11 days after the killings. He interviewed Ms. Clancy 45 times. Over 35 hours, he reconstructed Ms. Clancy’s depression, mood instability, and postpartum psychosis. She believed strangers could read her thoughts. She felt compelled to kill the children and herself. During a phone call to her husband, Dr. Zeizel heard her tell him that a male voice commanded her to kill the children. He diagnosed Ms. Clancy with postpartum psychosis and bipolar II disorder, concluding that a mental disorder impaired her ability to appreciate the moral wrongfulness of her actions.

Defense forensic psychiatrist Dr. Phillip Resnick, an expert on maternal filicide, examined Ms. Clancy four months after the killings for three hours. He diagnosed severe depression, bipolar II disorder, suicidal intent, and postpartum psychosis, manifested by a command hallucination. She was preoccupied with her children’s welfare, believing they could not live without her, which is characteristic of altruistic filicide. He described........

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