HOUSTON — Shortly after noon Wednesday, jurors in Andrea Yates’ murder retrial returned a verdict of not guilty by reason of insanity.

Earlier Wednesday jurors asked to see a family photo and candid pictures of her five smiling youngsters taken before she drowned them in the family bathtub.

Jurors have deliberated about 12 hours so far. Soon after arriving at the courthouse Wednesday, the jury of six men and six women also reviewed the state’s definition of insanity: that someone, because of a severe mental illness, does not know a crime he is committing is wrong. They had asked the court late Tuesday to go over that definition again.

In Yates’ first trial in 2002, jurors deliberated nearly four hours before convicting her in the children’s drowning deaths. That conviction was overturned on appeal last year.

Yates, 42, has pleaded innocent by reason of insanity. She is charged in only three of the deaths, which is common in cases involving multiple slayings.

As court was to end Tuesday, jurors asked for one more hour to deliberate. But then the panel immediately passed another note rescinding that request. State District Judge Belinda Hill quoted the note, which read, “We need some sleep,” prompting laughs from those in the courtroom.

The jury earlier asked to review the videotape of Yates’ July 2001 evaluation by Dr. Phillip Resnick, a forensic psychiatrist who testified for the defense that she did not know killing the children was wrong because she was trying to save them from hell.

Resnick told jurors that Yates was delusional and believed 6-month-old Mary, 2-year-old Luke, 3-year-old Paul, 5-year-old John and 7-year-old Noah would grow up to be criminals because she had ruined them.

Jurors later asked to review Yates’ November 2001 videotaped evaluation by Dr. Park Dietz, the state’s expert witness whose testimony led an appeals court to overturn Yates’ 2002 capital murder conviction last year.

Dietz, a forensic psychiatrist, testified in her first trial that an episode of the television series “Law & Order” depicted a woman who was acquitted by reason of insanity after drowning her children. But no such episode existed. The judge barred attorneys in this trial from mentioning that issue.

On Tuesday, after jurors asked for the trial transcript involving defense attorney George Parnham’s questioning of Dietz about the definition of obsessions, the judge brought the jury back into the courtroom.

The court reporter then read the brief transcript, in which Dietz said Yates “believed that Satan was at least present. She felt or sensed the presence.” Dietz had testified that Yates’ thoughts about harming her children were an obsession and a symptom of severe depression — not psychosis.

Earlier Tuesday, jurors reviewed the slide presentation of the state’s key expert witness, Dr. Michael Welner, a forensic psychiatrist who evaluated Yates in May. He testified that she did not kill her children to save them from hell as she claims, but because she was overwhelmed and felt inadequate as a mother.

Welner told jurors that although Yates was psychotic on the day of the June 2001 drownings, he found 60 examples of how she knew it was wrong to kill them.

If Yates is found innocent by reason of insanity, she 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 be told that.