When Can a Judge Throw Out a Jury’s Verdict?

In San Francisco this week, a judge threw out a jury’s second-degree murder conviction of Marjorie Knoller, the woman whose dogs mauled a neighbor to death. When can a judge throw out a verdict? And what’s to stop him from doing so every time he disagrees with the jury’s decision?

A judge may only throw out guilty verdicts. He may never overrule a jury that acquits a defendant and then himself declare the defendant guilty.

While the law varies from state to state, a judge usually throws out guilty verdicts for one of two reasons: 1) a jury returns a verdict for which there was not enough evidence to find the defendant guilty beyond a reasonable doubt; or 2) a mistake or wrongdoing by one of the participants poisons the whole trial.

The San Francisco case was an example of the first reason. The judge concluded Knoller could not have known her dogs would kill someone, so she did not possess the mental state required to commit murder under California law. Similarly, the judge who presided over the 1997 baby-shaking trial of British nanny Louise Woodward reduced the jury’s second-degree murder verdict to involuntary manslaughter. He found no malice in Woodward’s actions, a necessary legal element to support the murder conviction in Massachusetts.

Alternatively, a judge can throw out a verdict for any mistake or malfeasance that might prompt a higher court to overturn it. Some examples include: prosecutors hiding evidence that might exonerate the defendant; a defense lawyer sleeping through the trial; a jury member doing outside research on the case; or the judge incorrectly instructing the jury on the law controlling the case and realizing his mistake after the fact.

What’s to stop a corrupt judge from throwing out guilty verdicts every time he disagrees with a jury? For one thing, prosecutors can always appeal the set-aside ruling to a higher court. For another, judges who abuse their power can be hauled before judicial ethics boards, which in extreme cases can rebuke or even remove a judge. And in the 39 states that elect their judiciary, tossing out a popular jury verdict could result in voters tossing out the judge.

Next question?

Explainer thanks Kent Scheidegger of the Criminal Justice Legal Foundation and Sabita Singh of the Boston law firm Bingham Dana. Thanks to Jonathan Weinberger for asking the question.