THE US: A psychiatrist who examined Ms Andrea Yates, the day after she drowned her five children, described her at her Houston trial as "one of the sickest patients I have ever seen" in 16 years and 6,000 patients.
Dr Melissa Ferguson, the psychiatrist at the Harris County jail who was the first professional psychiatrist to examine Ms Yates after the killings last June, told the court Ms Yates "had no insight whatever into the severity of her medical illness" and in fact denied that she was ill. Instead, Ms Yates had described herself that day as "Satan".
"She was convinced that her children were tainted and doomed to suffer in the fires of hell," Dr Ferguson testified. "She said they had to die to be saved."
The doctor had diagnosed Ms Yates as suffering from major depression with psychotic features triggered by the births of her children, and suggested that she might also be a paranoid schizophrenic. Ms Yates claimed to be hearing voices and believed she was being watched secretly by the media.
Under Texas law the prosecution only has to prove that at the time of the killings she knew the difference between right and wrong.
To that end prosecutors have emphasised evidence of planning. The assistant district attorney, Ms Kaylynn Williford, asked: "Do you remember her making a statement: 'After thinking about my options, I decided drowning would be the best way to end their life'?"
Ms Yates said "something about drowning, that drowning was the way," Dr Ferguson replied. Asked by Ms Williford if she recalled Ms Yates saying, "I decided a knife was too bloody," Dr Ferguson said "yes".
Dr Ferguson testified Ms Yates told her she thought about killing her children for at least three months and thought about it the night before the children were drowned.
Dr George Ringholz, a neuropsychologist, also testified that Ms Yates told him she felt Satan's presence shortly after the birth of her eldest son, Noah.
"She heard Satan's voice tell her to pick up the knife and stab the child," Dr Ringholz testified, adding Ms Yates's comments were typical of schizophrenia.
He said he was prepared to testify Yates was insane when she drowned her children.
Mr John Bayliss, a jail nurse, said Ms Yates thought she may have been hearing voices in the weeks after she was jailed. "She was a person who wasn't connected with reality at all," he said.
Ms Yates is on trial on two counts of capital murder for the deaths of three of her five children. Prosecutors are seeking the death penalty in the deaths of Noah (7), John (5) and six-month-old Mary. Charges could eventually be filed in the deaths of Paul (3) and Luke (2).
The prosecution finished its case on Friday after four days of testimony from police officers, homicide detectives, a crime-scene specialist and the 911 emergency operator who took Ms Yates's call.