While making the case against statutory reform, St. John offers several reasons why nullification is unjust. The first: it is patently undemocratic.
Proponents of jury nullification have convincingly argued that nullifying juries make law. Although they would conclude from this that the jury might be understood as a lawmaking body parallel--or even superior--to the legislature,I will argue that this insight demonstrates the crucial and fatal flaw in the case for enactment of the jury nullification power. When legislatures delegate to juries the right to make law, the law becomes not more but less democratically legitimate.Why is this?
[J]uries can neither represent nor embody the community or its will. Not only do juries fail to reflect an adequate demographic sample of the community, but their voting rules make them minoritarian rather than majoritarian bodies. It is impossible to reform their minoritarian nature without undermining what little confidence we do have in their verdicts' representativeness.The paradox of supermajorities in all forms, of course, is the same: they tip the scales toward dissenters. St. John also notes that the "minorities" in the jury room are not even necessarily minorities in the wider community, which doubly means that the the mistrial (or, possibly, reduced charge) that results from a hung jury will not reflect the community's wishes.
Of course, this argument doesn't apply to someone who justifies jury nullification on other grounds--or someone who limits jury nullification in principle to a unanimous acquittal.
What, then of the argument that "jury mercy" is a way of reducing government power?
Central to the theory of the "jury veto" is an understanding of nullification as having the potential only to aid the criminal defendant. Although this claim is often made in the abstract, it is also made by those who would seek an open, legislatively enacted form of jury nullification. In order to protect individual liberties, this argument runs, the entire criminal justice system is stacked in favor of the defendant; if the jury, or any other coordinate actor in the process, refuses to convict the defendant, she will be set free. According to one proponent of this view, the jury's exercise of its "power to acquit, notwithstanding overwhelming evidence of guilt... is simply an act of mercy to a particular defendant in a specific case." This definition of nullification as "jury mercy" is not uncommon in the literature. However, the concept is gravely mistaken on three levels. First, on an empirical level, nullifying juries can exercise vengeance as well as mercy; in nearly all recent proposals for nullification, little restraint would be placed on the jury's ability to penalize defendants. Second, on a theoretical level, our criminal justice system serves important ends that would be neglected were guilty defendants to be freed by jury "veto."... Finally, even though we ought to be concerned about the discretion other actors can exercise, additional jury discretion is a dangerous and unsatisfying remedy.The prohibition of "double jeopardy," the fact that jury deliberations are private, and the fact that jurors cannot be held liable for their verdict, means that juries can act with little accountability.