Definition
In civil law, *communis paries* (also rendered *communis pares* in older English legal sources) refers to a party wall — that is, a wall shared between two adjoining properties, standing on the boundary line and serving both owners simultaneously. The wall is held in common, with each owner possessing a right of use and an obligation not to damage or destroy the shared structure to the detriment of the other. The concept derives from Roman civil law and passed into the legal systems of Continental Europe and, through equity and early common law borrowings, into Anglo-American property doctrine.
Common Confusion
The term *communis pares* is frequently confused with *communis* used broadly to mean anything held in common, but the phrase in legal usage is specific: it refers to a wall, not a general common property arrangement. Researchers encountering *communis* alone in Latin legal texts should not assume it carries the same meaning as this compound term. Additionally, the rendering *pares* rather than *paries* appears in some older English legal dictionaries as a transliteration artifact; both refer to the same concept, but *paries* (wall) is the correct Latin noun.
Why It Matters in Research
This term appears almost exclusively in sources engaging with civil law tradition — Roman law commentaries, early English equity materials, and treatises on property law written before American and English doctrine had fully consolidated its own party wall vocabulary. Researchers working with colonial-era property disputes, early American land records influenced by French or Spanish civil law (Louisiana, Florida, the Southwest), or English equity cases from the seventeenth and eighteenth centuries are the most likely to encounter it.
The practical trap: English and American common law developed its own party wall doctrine largely independently, using common-law terminology that does not map perfectly onto the civil law concept. A researcher who finds *communis pares* in a historical source and immediately imports modern party wall doctrine to interpret it may introduce anachronism. The civil law conception of the shared wall emphasized the communal nature of ownership; common law party wall doctrine often treated the wall as two separately owned halves with mutual easements — a materially different legal structure.
Corpus researchers should also note that the term drops out of active use in American legal literature well before the twentieth century. Its appearance in a source is itself a dating and jurisdictional signal: the author was likely writing within or consciously drawing on civil law tradition, not mainstream Anglo-American common law.
Historical Dictionary Support
Rapalje and Lawrence give a compressed but accurate entry: "In the civil law, a party wall." The brevity is characteristic of their treatment of civil law terms that had limited active use in American litigation by the time their dictionary was compiled. The entry confirms the term's civil law provenance and its equivalence to the party wall concept, but offers no analysis of how the civil law treatment differs from common law party wall doctrine — a gap researchers should keep in mind.
No other major English-language legal dictionaries in the Law Mind corpus provide extended treatment of this term. The scarcity itself is informative: by the late nineteenth century, American legal writers had largely displaced the Latin civil law vocabulary with English-language party wall doctrine, and *communis pares* had become an antiquarian reference rather than a working term of art.
Jurisdictional Note
The term carries the most weight in jurisdictions with sustained civil law influence — particularly Louisiana, where party wall doctrine has historically tracked civilian concepts more closely than in common law states. Researchers working in other American jurisdictions should treat the term as historical rather than operative.