[12] Nullification is not an official part of criminal procedure, but is the logical consequence of two rules governing the systems in which it exists: A jury verdict that is contrary to the letter of the law pertains only to the particular case before it; however, if a pattern of acquittals develops in response to repeated attempts to prosecute a particular offence, this can have the de facto effect of invalidating the law.
Similarly, juries are routinely cautioned by courts and some attorneys not to allow sympathy for a party or other affected persons to compromise the fair and dispassionate evaluation of evidence.
In the United States, some view the requirement that jurors take an oath to be unlawful in itself, while still others view the oath's reference to "deliverance" to require nullification of unjust law: "will well and truly try and a true deliverance make between the United States and the defendant at the bar, and a true verdict render according to the evidence, so help [me] God".
[26] Some lawyers use a shadow defense to expose the jury to information that would otherwise be inadmissible, hoping that evidence will trigger a nullification.
Juries were composed primarily of "laymen" from the local community and provided a somewhat efficient means of dispute resolution with the benefit of supplying legitimacy.
The general power of juries to decide on verdicts was recognised in the English Magna Carta of 1215,[29] which put into words existing practices: No free man shall be captured, and or imprisoned, or disseised of his freehold, and or of his liberties, or of his free customs, or be outlawed, or exiled, or in any way destroyed, nor will we proceed against him by force or proceed against him by arms, but by the lawful judgment of his peers, or by the law of the land.
None of these fines shall be imposed except by the assessment on oath of reputable men of the neighbourhood.Largely, the earliest juries returned verdicts in accordance with the wishes of the judge or the Crown.
Lilburne had been charged with seditious libel for the publication of articles critical of the government; the jury were instructed to give a verdict only on whether the text was published, and to leave the issue of libel to the judge, while Lilburne argued the jury should give a general verdict and should judge whether the law's restraint on speech against the government was just.
This view was not shared by the jury, which, after three days' hearing, acquitted Lilburne—who had defended himself as skillfully as any lawyer could have done—to the great horror of the Judges and the chagrin of the majority of the Council of State.
[30]In 1653, Lilburne was on trial again and asked the jury to acquit him if it found the death penalty "unconscionably severe" in proportion to the crime he had committed.
[31] In 1670, a petit jury refused to convict William Penn of unlawful assembly for religious practice not associated with the Church of England.
To avert that injustice, the jury decided to assert what it believed to be its "ancient right" to judge the whole case, not just the facts, and rendered the verdict of "not proven".
Perhaps the most famous cases of jury nullification in Canada were the various trials of Henry Morgentaler, who openly operated a private abortion clinic in violation of the Criminal Code.
In obiter dicta, Chief Justice Dickson wrote: The contrary principle contended for by Mr. Manning, that a jury may be encouraged to ignore a law it does not like, could lead to gross inequities.
Penn and William Mead had been arrested in 1670 for illegally preaching a Quaker sermon and disturbing the peace but four jurors, led by Edward Bushell, refused to find them guilty.
It is the duty of the Judge, in all cases of general justice, to tell the jury how to do right, though they have it in their power to do wrong, which is a matter entirely between God and their own consciences.
– That the law shall be, in every particular cause, what any twelve men, who shall happen to be the jury, shall be inclined to think; liable to no review, and subject to no control, under all the prejudices of the popular cry of the day, and under all the bias of interest in this town, where thousands, more or less, are concerned in the publication of newspapers, paragraphs, and pamphlets.
Three years later a civil servant, Clive Ponting, leaked two government documents concerning the sinking of the cruiser to a Member of Parliament (Tam Dalyell) and was subsequently charged with breaching section 2 of the Official Secrets Act 1911.
[40] The prosecution in the case demanded that the jury convict Ponting, as he had clearly contravened the Act by leaking official information about the sinking of the Belgrano during the Falklands War.
[43] In 2021, six activists associated with the environmental protest organisation Extinction Rebellion were tried for causing criminal damage to the British headquarters of the multinational oil company Royal Dutch Shell.
The judge told the jury that there was 'no defence in law' for the protestors' actions, which according to the prosecutor had caused 'significant damage' to the building, but the activists were acquitted.
[44][45] In 2023, Insulate Britain members Giovanna Lewis and Amy Pritchard were jailed for seven weeks after defying the judge's ban on informing the jury of the reasons for their actions.
[47] Following juries acquitting activists, dozens of people have been threatened with arrest for displaying signs that remind jurors of their right to make decisions based on conscience.
[53][54] However, although the moral dimension of the case was strongly emphasised by the defense, the acquittal was based on a plead of temporary insanity and there was no dissent between court and jury.
He wanted high-profile convictions, but the jury nullifications ruined his presidential aspirations and his last-ditch efforts to find a compromise between North and South.
[60] White defendants accused of crimes against black people and other minorities were often acquitted by all-white juries, especially in the South, even in the face of irrefutable evidence.
[64] In the 1895 case of Sparf v. United States, written by Associate Justice John Marshall Harlan, the US Supreme Court held 5-4 that a trial judge has no responsibility to inform the jury of the right to nullify laws.
In some states, jurors are likely to be struck from the panel during voir dire if they do not agree to accept as correct the rulings and instructions of the law as provided by the judge.
[67] In 1972, in United States v. Dougherty, 473 F.2d 1113, the United States Court of Appeals for the District of Columbia Circuit issued a ruling similar to Moylan that affirmed the de facto power of a jury to nullify the law but upheld the denial of the defense's chance to instruct the jury about the power to nullify.
[69] In 2002, South Dakota voters rejected by a 78% margin a state constitutional amendment to permit criminal defendants to argue for jury nullification.