The U.S. Supreme Court on Monday reinstated a conviction against a woman charged with shaking her grandson to death, criticizing a federal appeals court's decision to overturn a jury's guilty verdict.

In a 6-3 decision, the justices found that a the U.S. Court of Appeals for the Ninth Circuit based in California substituted its judgment for that of a California jury in weighing testimony of expert witnesses in a criminal case against the dead infant's grandmother, Shirley Ree Smith.

Doubts about whether Smith is in fact guilty are understandable. But it is not the job of this court and was not that of the Ninth Circuit, to decide whether the state's theory was correct, the Supreme Court majority wrote. The jury decided that question, and its decision is supported by the record.

This was the third time the Supreme Court reversed the Ninth Circuit's decision in this case, calling the judges'; attention to high court cases that support deference to state court verdicts. After each decision from the high court, the lower appellate court reinstated its judgment without considering the Supreme Court's concerns.

Autopsy Concluded that Death Was Shaken Baby Syndrome

In 1996, Smith was charged with the death of her grandson, Etzel Glass, who was 7-weeks old at the time of death. An autopsy concluded that the cause of death was shaken baby syndrome. After seven days of expert medical testimony on the infant's cause of death, Smith was found guilty and sentenced to 15 years to life in prison.

Smith fought the conviction in California's trial and appellate courts, but was unsuccessful. She then petitioned a federal court based in Los Angeles, arguing that the evidence at trial was insufficient to prove that her grandchild died of a torn brain stem caused by shaking.

The federal district court rejected her petition but the Ninth Circuit appellate court ruled in Smith's favor. The Ninth Circuit criticized the evidence that led to shaken baby syndrome as the cause of death, noting the lack of evidence supporting a torn brain stem.

Without physical evidence proving that Etzel Glass' brain stem was torn, the Ninth Circuit tossed the jury verdict.

There simply was no evidence to permit an expert conclusion one way or the other on the point, the Ninth Circuit wrote in its 2006 opinion overturning Smith's conviction. This is simply not the stuff from which guilt beyond a reasonable doubt can be established, especially in the face of all the other circumstances... making the crime unlikely.

Justice Ginsburg's Dissent: Meager Nonmedical Evidence

Justice Ruth Bader Ginsburg, writing for Justices Stephen Breyer and Sonia Sotomayor in the minority, backed the Ninth Circuit's decision to overturn a state jury verdict was accurately based on the law allowing for such decisions.

By taking up the case, one may ask, what does the court achieve other than to prolong Smith's suffering and her separation from her family, Ginsburg wrote. Is this court's intervention really necessary? Our routine practice counsels no.

Ginsburg, too, criticized the state's meager nonmedical evidence against Smith regarding her motive and her poor legal counsel.

The justice said that the majority is bent on rebuking the Ninth Circuit for its defiance.

I would not ignore Smith's plight and choose her case, Ginsburg wrote, as a fit opportunity to teach the Ninth Circuit a lesson.