Andrea Yates, the Texas woman convicted in 2002 of drowning her five children in a bathtub, while suffering from postnatal depression, has been granted a new trial, after it was found that an expert medical witness for the prosecution had lied at her original trial.
Dr Park Dietz, a mental health expert who appeared for the prosecution, who was also a consultant for the television programme Law and Order , had told the trial court jury that there was an episode of that programme, in which a woman with postpartum depression, who drowned her children in the bath, was found insane. He said it was aired shortly before Ms Yates carried out the same actions.
A three judge appeals court panel in Houston said last week that the statement was false; there was no such episode. The falsehood had been discovered shortly after the jury convicted Ms Yates, but before she was sentenced. The jury was told about the falsehood during the sentencing hearing, at which Ms Yates received life imprisonment. The prosecution had pushed for the death penalty.
The trial court then denied a defence application for a mistrial, but the appeal court panel said that the application should have been granted. While absolving them of wrongdoing, the appeal panel said prosecutors "connected the dots" with the false testimony to convince jurors that Ms Yates, who watched the television series, patterned her actions after the episode.
The panel wrote, "We conclude that there is a reasonable likelihood that Dr Dietz's false testimony could have affected the judgment of the jury. We further conclude that Dr Dietz's false testimony affected the substantial rights of appellant."
Judge Sam Nuchia wrote, "Although the record does not show that Dr Dietz intentionally lied in his testimony, his false testimony undoubtedly gave greater weight to his opinion."
Dr Dietz, who was the only mental health expert who appeared for the prosecution, was also the only witness to testify that Ms Yates, could tell the difference between right and wrong (BMJ 2002 ;324:634,694 ). Five other mental health experts said she did not know right from wrong, or that she thought drowning her children was right.
Prosecutor Joseph Owmby , said his office would ask the 3-judge panel to reconsider. If that fails, prosecutors will ask the full Appeals Court, and then the Court of Criminal Appeals (the state's highest court) to reverse the panel's decision.
At the time of her trial, Ms Yate's case sparked nation-wide debate over the legal standard for mental illness, and whether postpartum depression is properly diagnosed. Women's groups had harshly criticized prosecutors for pushing for the death penalty