Puts this one in a "too silly to be true" category.  According to this article at the law.com site, a Texas intermediate appellate court overturned a murder conviction of Andrea Yates.  Ms Yates made the headlines several years ago, when she was charged with and convicted of drowning her kids in a bathtub.  The reason for the reversal is a testimony of one of the prosecution's experts, who told the jury (in some unspecified context) that sometime prior to the murders, an episode of Law and Order was aired, in which a woman was accused of drowning her kids and claimed insanity.  I guess the expert was trying to say that Ms. Yates got her inspiration for the murders and the insanity defense from that episode.

Now, to me, when the prosecution starts to rely on "Law and Order" episodes, this means it does not have a strong case.  (Editorial Note - I like the show, particularly when Jill Hennessee and Carry Lowell were on, despite the fact that  it showed 95 % of the defense bar to be obnoxious money-grubbing freaks).  However, to make matters worse, in this case, the "Law and Order" reference was false - no such episode was ever shown.