In the United States juries are not informed by the judge of their right to nullification because the case law addressing jury nullification remains oblique. It is therefore commonly said that in the United States juries are empaneled to resolve issues of fact, but when it comes to nullification, juries have the right but not the power to judge the law. Consequently, a judge will never directly instruct a jury than they judge the law. The reverse is also true; a judge will not instruct a jury that they may not judge the law. In a criminal case, the litigants are also precluded from advising the jury of their right to nullification.
When looking at the history of nullification in the Untied States, it is clear that while the breadth of jury nullification in our criminal justice system has ebbed and flowed it has never entirely gone away. Today a jury sitting on a criminal case may engage in nullification. Since nullification remains a part of our criminal justice system, the question that obtains is this; how much influence can, or should, the judiciary have in limiting or otherwise influencing the jury’s right to nullify? Said differently, as “keepers of the law,” what role do judges have in explaining or refuting nullification?
In looking at the question of whether or not jurors should be informed of their right to nullify, Irwin A. Horowitz has this to say:
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