It will be especially difficult for Schenecker because she purchased a handgun five days before the shootings, then picked it up after the three-day waiting period and soon used it to kill.
But court documents show that Schenecker has a long history of mental illness. In the early 1990s, she was diagnosed with depression and treated with medication. From 1997 to 2001, she was medicated daily except for when she was pregnant and nursing, records show.
In 2001, she suffered a debilitating bout of depression and was hospitalized for nine months. Documents also show that she was diagnosed with bipolar disorder, schizo-affective disorder and severe depression.
A few months before the killings, Calyx called the police on her mother, saying she had hit her. Police closed the case as there were no marks on the girl. The family was in counseling about a month before the killings.
Dekle points out that "being mentally ill doesn't prove someone is insane," and the two terms are not interchangeable in court.
"Mental illness is a medical concept," he said. "Insanity is a legal concept."
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