Yates was found guilty of two counts of capital murder covering the deaths of three of her children. She could be sentenced to death or to life in prison following the penalty phase that begins Thursday.
Standing between her attorneys, Yates showed little reaction as the judge read the verdict. Her husband, Russell, muttered, "Oh, God" and buried his head in his hands, and some of Yates' relatives left the courtroom in tears.
"I'm not critiquing or criticizing the verdict," defense lawyer George Parnham said. "But it seems to me we are still back in the days of the Salem witch trials."
He described his client as "very upset." Prosecutors left the courthouse without comment.
The crime attracted widespread attention as a stunned public asked what could cause a mother to systematically kill her children. It also raised new questions about the effects of postpartum depression, which Russell Yates and experts hired by the defense said Yates had struggled with for years.
Andrea Yates never testified. But her videotaped interviews with psychiatrists, her audiotaped confession to police and her 911 call the day of the drownings all were played for jurors.
Deliberations began after prosecutors told the jury of eight women and four men that Yates, a former nurse, had thought about harming her children for years and ignored a doctor's orders in 1999 to refrain from having any more.
"That's the key," prosecutor 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 defense argued that she suffered from postpartum 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," Parnham said. "She was so psychotic on June 20 that she absolutely believed what she was doing was the right thing to do."
Parnham also told the jury in the closely watched case: "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."
After deliberating about 21/4 hours, jurors passed a note to District Judge Belinda Hill asking for the definition of insanity. Thirty minutes later, jurors asked for a cassette player. Among the evidence were the audiotapes of her 911 call and her confession in which she described how 7-year-old Noah tried to run from her, but "I got him."
Yates called her children into the bathroom one by one and drowned them in the tub, then called 911 to tell authorities what she had done. Police found Noah in the tub; the other children were under a wet sheet on a bed.
According to testimony, 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.
One count listed the killings of Noah and John as two victims killed during the commission of the same crime to qualify for capital punishment. The second count listed the death of Mary.
By not listing all the children in a single count, prosecutors avoided the possibility that an acquittal could void all the charges. Prosecutors also have the option of filing charges later in the deaths of the other two youngsters, Paul, 3, and Luke, 2.
Much of the trial was spent on the definition of insanity, and expert witnesses disagreed on that point.
An expert for the defense told the jury that while 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 Yates did not start referring to Satan until the day after her arrest. Williford argued 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.
Yates sobbed quietly as Williford described the condition police found her children.