Stephanie Rochester is accused of first-degree murder in the June 2010 death of her son, Rylan, and has pleaded not guilty by reason of insanity.
Both a psychiatrist hired by the defense and a state psychiatrist appointed by the court have ruled she was legally insane at the time of the child's death.
"Given the Court's ruling and the state of the evidence in the case at this time, I have determined that there is not sufficient admissible evidence for the prosecution to meet its burden of convincing a jury of 12 to reach a unanimous decision, beyond a reasonable doubt, that Stephanie Rochester was legally sane when she allegedly killed her infant son. That is the legal standard in a case in which a defendant has pled not guilty by reason of insanity, and based on that, I have determined that it is inappropriate to proceed to a jury trial in this case," Boulder County District Attorney Stan Garnett said in a statement on Monday.
Rochester's neighbors said at the time of the arrest they believed she had postpartum depression.
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