Definition
To labour a jury is to tamper with jurors or otherwise improperly influence them in the discharge of their duty — whether by persuasion, bribery, intimidation, or solicitation — with the intent of affecting the verdict they return. The conduct could be directed at jurors individually or collectively, and could occur before or during trial. The term encompasses efforts both to corrupt a juror's judgment on the merits and to prevent jurors from appearing or serving at all.
The modern equivalent is jury tampering or jury interference, which is treated as a serious criminal offense and a contempt of court in virtually all common law jurisdictions.
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Common Language
Modern common usage (Wiktionary): "Labour" (or "labor") means to work hard or to toil; to exert effort toward a task. No common legal meaning attaches to the phrase "labour a jury" in modern usage.
Historical common usage (Webster's 1913): To labor: "To work; to toil; to exert one's powers of body or mind in the performance of some task." The phrase "labour a jury" does not appear in general usage dictionaries of the period.
The legal meaning has no ordinary-language counterpart. The phrase borrows "labour" in its sense of diligent exertion, but turns it to describe illicit effort — working on jurors to corrupt their function. A researcher encountering this phrase for the first time might read it as neutral industry rather than criminal misconduct.
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Common Confusion
"Labour a jury" should not be confused with legitimate jury preparation, such as jury consulting, voir dire strategy, or witness preparation. The distinction is the improper and extrajudicial nature of the contact. Similarly, the term should not be conflated with jury nullification, which describes the jury's own independent decision to acquit against the weight of evidence — a unilateral act by the jury rather than external interference with it.
In historical sources, the phrase also occasionally describes efforts to prevent jurors from appearing at all (as in the Burrill example), not merely to corrupt the verdict of those who do appear. Researchers should read the context carefully to determine which form of interference is alleged.
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Why It Matters in Research
This is an archaic term of art confined almost entirely to old English practice materials and early common law reports. It will not appear in modern statutes or contemporary case law under this label. Researchers working in pre-nineteenth-century English legal records, early American colonial practice, or historical equity proceedings may encounter it and need to recognize it as the forerunner of modern jury tampering doctrine.
The phrase is characteristic of the Year Books and the early reporters (Dyer, Leonard, Plowden) and reflects a period in which jury practice was deeply entwined with personal influence, social obligation, and local power. The conduct it describes — having friends, servants, or retainers approach jurors on behalf of a litigant — was a recognized abuse well before systematic procedural remedies existed.
For research purposes: if you are working backward from a modern jury tampering charge or contempt proceeding to its historical roots, this term is the bridge. Conversely, if you are reading early chancery or King's Bench records and encounter this phrase, understand that it signals serious procedural misconduct, often treated as a matter for the court's extraordinary jurisdiction rather than ordinary pleading.
Cross-corpus alert: connections to grand jury proceedings are indirect at best — the term appears in the context of petty (trial) juries, not grand juries. Do not assume encyclopedia entries on grand jury function (criminal_168, criminal_169) will illuminate this term's historical application.
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Historical Dictionary Support
Burrill's Law Dictionary is the primary source for this entry and gives the clearest definition available in the historical legal dictionary corpus: "to tamper with a jury; to endeavor to influence them in their verdict, or their verdict generally." Burrill's illustrative quotation — drawn from 1 Leonard 72 — depicts the conduct at its most concrete: Heydon's friends and servants were engaged to prevent jurors from appearing. This is significant because it shows the offense was not limited to corrupting the verdict of seated jurors but extended to obstruction of jury service itself.
Burrill also cross-references Dyer 48, indicating the concept was recognized in mid-sixteenth-century English practice. No other standard historical legal dictionaries in the corpus — including Bouvier, Black, or Jacob — contain entries under this precise phrase, making Burrill the authoritative shelf source for it. Researchers should treat any definition outside Burrill as derivative or inferential.
What the historical dictionaries do not address: the procedural consequences of the offense, the remedies available to a party whose jury was laboured, or whether the resulting verdict was voidable. Those questions require recourse to the reports themselves.
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Jurisdictional Note
The term is native to English common law and reflects pre-modern English procedure. American courts did not adopt this specific phrase, though the underlying conduct — jury tampering — was recognized as a common law offense in early American jurisdictions and has since been codified broadly. Researchers working in Scots law or civil law jurisdictions will find no direct equivalent.
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Encyclopedia Cross-Reference
The Law Mind Criminal Law Encyclopedia — Mistrial and Hung Jury (criminal_212): relevant for understanding modern consequences when jury integrity is compromised.
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