A US jury was today sent out to deliberate a 37-year-old mother was in her right mind when she drowned her five children in the bath.
Prosecutors in Houston, Texas are seeking the death penalty for Ms Andrea Yates, who pleaded not guilty by reason of insanity.
If acquitted, the court will decide whether she should be committed to a mental hospital or go free.
Deliberations began after prosecutors told the jury of eight women and four men that even though Ms Yates was mentally ill, she knew drowning her children was wrong and was therefore guilty of murder.
"That's the key," prosecutor Ms Kaylynn Williford said. "Andrea Yates knew right from wrong, and she made a choice on June 20 to kill her children deliberately and with deception."
The defence argued that Ms Yates suffered from postnatal depression so severe that she had lost her ability for rational thought.
"We can't permit objective logic to be imposed on the actions of Andrea Yates," defence lawyer Mr George Parnham said. "She was so psychotic on June 20 that she absolutely believed what she was doing was the right thing to do."
Mr Parnham also told the jury: "This is an opportunity for this jury to make a determination about the status of women's mental health. Make no mistake, the world is watching."
Last year, Ms Yates called her five children into the bathroom one by one and drowned them in the tub, then called police to tell them what she had done. Police found seven-year-old Noah in the tub; the other children were under a wet sheet on a bed.
According to testimony, Ms Yates was overwhelmed by the responsibilities of raising five children and believed she was a bad mother. She had suffered severe depression and had attempted suicide.
She is charged over the deaths of Noah, five-year-old John and six-month-old Mary. Charges could be filed later in connection with the deaths of Paul, three, and Luke, two.
To prove insanity, the jury must be convinced Ms Yates could not tell right from wrong.
Expert witnesses disagreed on that point.
An expert for the defence told the jury that while Ms Yates knew drowning her children was illegal, in her delusional mind she thought it was the only way to save her children from eternal damnation.
Prosecutors said Ms Yates did not start referring to Satan until the day after her arrest.
Ms Williford argued that Ms Yates was so deliberate she covered the bodies as she went because the children still alive were old enough to escape from the house and get help.
She also noted bruises the children suffered as they struggled with their mother.
AP