Jurors can't be charged with this because there is no way to prove it. And the jurors themselves wouldn't be prosecuted, by the way; it's been common-law doctrine for centuries that jurors are not to be prosecuted for anything they do in the rightful capacity as jurors. If a jury were found to have engaged in nullification, the result would be the overturning of their verdict as null. And even that would carry its own slew of double jeopardy issues.
Jurors are called upon to make decisions. Trying to prove that they made a given decision by using a certain rationale is tantamount to attempting to prove a thoughtcrime. This isn't your average state-of-mind issue, either: the result that a jury reached is one that they can legitimately reach. Juries are not held to their results. This isn't like negligence or premeditation. You actually have an objectively viewable red flag in criminal or tort cases that use those concepts.
A prohibition on jury nullification would be impossible to enforce and so can't really be made illegal. It is therefore recognized as a power, albeit one to be exercised under the radar. But it has no legal sanction whatsoever, and therefore cannot be recognized as a right.
Ummmm, I thought the whole point of jury nullification was at that point when the Foreman stood up and said, "Your Honor, we of the jury find that this law is unconstitutional and is hereby declared null and void."
Thereby freeing society from the burden of an unfair law, not merely releasing one victim of that law, and leaving the rest of us exposed the the whims of our local 'betters"...
A prohibition on jury nullification would be impossible to enforce and so can't really be made illegal.
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As stated above, nullification could be stopped by allowing judicial review. The courts have ruled jury nullification is legal. The congress has not tried to stop it by law or Constitutional amendment.
Jurors can't be charged with this because there is no way to prove it. And the jurors themselves wouldn't be prosecuted, by the way; it's been common-law doctrine for centuries that jurors are not to be prosecuted for anything they do in the rightful capacity as jurors. If a jury were found to have engaged in nullification, the result would be the overturning of their verdict as null. And even that would carry its own slew of double jeopardy issues.
The case of William Penn came to mind while thinking about this, and I searched around a bit to refresh myself of the facts of the case. I found the following Here:
Supporters of the informed jury movement usually go back to the John Peter Zenger libel case to bolster their position. Zenger was a New York printer who in 1735 published a series of pamphlets criticizing the colonial governor of New York. He was charged by the crown with "seditious libel," and at the time the definition of libel was the publication of anything criticizing public officials, laws or the government.
The judge in the case, quite rightly, ruled that the only fact matter to be proven was: Did he publish the articles or not? Everyone, including Zenger, agreed that the articles had been published and that they contained criticism, so there was no reason to put on evidence. Nevertheless, Zenger's attorney Andrew Hamilton argued that the articles were also true, and urged the jury to acquit on that basis. The jury ignored the law and acquitted Zenger, thereby establishing a principle that was later made law: truth is an absolute defense against libel charges.
But I think there's an even better case. In 1670 William Penn was indicted for preaching Quakerism under the "unlawful assembly" act. Despite the fact that he was obviously guilty according to the judge's interpretation of the law, four of the 12 jurors voted to acquit him. The judge had the jurors thrown in jail and starved for four days in an attempt to change their votes. It didn't work. Reluctantly, he ordered Penn released--but the crown still wasn't finished with the recalcitrant jurors.
The four who voted for innocence were assessed fines for failing to follow the law and sent to prison until the fines should be paid. Three chose to pay the fine--just to get things over with. The fourth juror, Edward Bushell, was of heartier stock and refused to pay. Instead he took his case to the Court of Common Pleas, where Chief Justice Vaughan eventually ruled that Bushell was right--jurors could not be punished for a verdict. If anything established that the jury was the sole arbiter of law and facts, it was this case.
There has been quite a bit of commentary about the meaning of the case against William Penn, much of it I've found at sites supporting FIJA (ya, FIJA sites are likely to be somewhat biased). It was apparently a rather ground-breakinng precident in the history of the common law, from whence much of our law comes. The very idea of a group of 12 jurors being able to completely overturn the entire leviathan mechanism of "The Law" strikes fear into a great many statists all across this nation of ours.
I think the argument I've seen here regarding jury nullification being a 'right' or a 'power' is, as you commented later on a moot point, as any member of the jury can choose to ignore the law if he so chooses.
Jury nullification was used to great effect in the years leading up to the civil war to protect those who would harbor fugitive slaves. It was similarly used quite often in many areas of the country during prohibition. In fact in many places, you couldn't get a conviction for moonshining because the people decided the whole thing was a bad idea. I find myself in a similar frame of mind with many laws. If on a jury, if I can't find a victim, (i.e., many drug laws, seatbelt laws, and similar things) I seriously doubt that my concience would allow me to convict.