For much of the past four weeks, jurors in Andrea Yates' murder trial have heard about how she spiraled from a dedicated nurse to a catatonic mental hospital patient, how she thought cartoon characters spoke to her through the television — and how on one summer morning she drowned her five children in the bathtub.

They heard an audiotape of Yates in a flat, emotionless voice answer a detective's questions a few hours later. The jury also saw segments of her videotaped interviews — at times emotional — with several state and defense psychiatrists who talked to Yates, one as recently as May.

On Monday, before jurors begin sorting through the evidence and testimony from 40 witnesses, they will hear once more from defense attorneys and prosecutors who each have two hours for their closing arguments.

Click here to visit FOXNews.com's Crime Center.

Defense attorneys say Yates suffered from severe postpartum psychosis when she killed 6-month-old Mary, 2-year-old Luke, 3-year-old Paul, 5-year-old John and 7-year-old Noah in June 2001. They say that in her delusional state, Yates thought Satan was living inside her and believed she had ruined the children so much that she had to kill them to save them from hell.

Prosecutors say that although Yates may be mentally ill, she fails to meet the state's definition of insanity: that a severe mental illness prevents someone who is committing a crime from knowing it is wrong.

They say she planned the crime for the small window of time when she'd be alone with the youngsters, after her husband went to work and before her mother-in-law arrived to help care for them. Then Yates called 911, led police to the bodies and told a detective she was a bad mother and wanted to be punished, according to testimony.

Yates, 42, is being retried because an appeals court overturned her 2002 conviction on the grounds that some erroneous testimony may have influenced jurors. Yates is charged in only three of her five children's deaths.

If found innocent by reason of insanity, Yates will be committed to a state mental hospital, with periodic hearings before a judge to determine whether she should be released — although by law, jurors are not allowed to know that.

Yates, who was her senior high school class valedictorian, will be sentenced to life in prison if convicted of capital murder.

A capital murder conviction in Texas carries either life in prison or the death penalty. Prosecutors could not seek death this time because the first trial's jurors sentenced her to life in prison, and authorities found no new evidence.

Click here to visit FOXNews.com's Law Center.