Definition
Vicini is a Latin term meaning "neighbors" or "of neighbors." In legal usage, it appears most prominently in the phrase in aemulationem vicini (sometimes rendered in emulatione vicini or in emulationem vicini), meaning "in envy or hatred of a neighbor." The phrase describes acts done not for any legitimate purpose of the actor's own, but solely or primarily to harm, annoy, or distress an adjoining landowner or neighbor. The doctrine holds that a person exercises rights in an aemulationem vicini when the motive is pure spite or malice rather than any genuine self-interest.
Why It Matters in Research
Researchers will encounter vicini almost exclusively in the phrase in aemulationem vicini rather than as a standalone term. The doctrine it anchors — that malicious exercise of an otherwise lawful right may give rise to liability — sits at the intersection of property law, nuisance, and the broader question of whether motive can defeat a legal right.
This is a point of significant jurisdictional divergence. Scots law and civil law systems historically gave the aemulationem vicini doctrine real operative force: a landowner in Scotland could be restrained from or held liable for an act done solely out of spite, even if the act would otherwise be lawful. English common law, by contrast, largely rejected the idea that malicious motive could convert a lawful act into an actionable wrong — the foundational principle being that if the act is within a legal right, the motive is generally irrelevant. American common law followed the English rejection, though some nuisance cases flirt with motive-based analysis.
Researchers reading historical sources, particularly older Scottish or civilian-influenced texts, should be alert to this divergence: a treatise citing the aemulationem vicini doctrine approvingly may be speaking from a Scots or civil law tradition that does not map cleanly onto English or American authority. Lord Kames, cited in Black's, is a Scottish jurist writing from within that civilian-influenced tradition — his Principles of Equity should be read accordingly.
The term also appears in older jury practice materials, where vicini referred to the neighborhood from which jurors were drawn — the community of persons from the vicinity who would have knowledge of local facts. This is a distinct and older usage rooted in early common law jury selection, and confusion between the two uses (the malice-of-neighbors doctrine and the jury-of-the-vicinity usage) is possible when reading pre-nineteenth century sources without context.
Historical Dictionary Support
Black's Law Dictionary defines vicini in the context of in emulatione vicini — "in envy or hatred of a neighbor" — and describes it as applying where an act is done or an action brought solely to hurt or distress another. Black's cites Lord Kames's Equity (volume 1, page 56), a Scottish authority, which signals that the compilers understood the doctrine's civilian pedigree.
Black's also pairs the entry with the maxim in eo quod plus sit, semper inest et minus ("in the greater is always included the less"), drawn from the Digest of Justinian. The pairing suggests the entry was organized around civilian legal sources rather than English common law authority, which is itself instructive about where this doctrine lives in the legal tradition.
Historical dictionaries do not resolve the tension between civil law acceptance and common law skepticism of the doctrine — that work falls to treatises and case law rather than dictionary entries. Researchers should treat the dictionary entry as a pointer to the doctrine's existence and civilian origins, not as a reliable guide to its reception in any particular jurisdiction.
Jurisdictional Note
The in aemulationem vicini doctrine has genuine operative force in Scots law and in some civil law jurisdictions. English and American common law have generally declined to recognize malicious motive alone as a basis for liability when the underlying act is otherwise lawful, though nuisance and abuse-of-rights doctrines in some American states echo the civilian concept.