Definition
Lucrativa causa is a Latin term from Roman law meaning a gratuitous or voluntary consideration — that is, a basis for acquiring property or rights founded on gift, bequest, or other liberality rather than on exchange or obligation. It stands in contrast to onerosa causa, which describes a valuable or onerous consideration grounded in mutual obligation, payment, or performance.
The concept operated primarily in the law of succession and property acquisition. A person who received something by lucrativa causa — through inheritance, legacy, or gift — acquired it without surrendering anything in return. This was not a defect; it was simply a classification of how title passed.
The most consequential rule associated with the term is the Roman law principle that two lucrative causes could not concur in the same person with respect to the same thing (duae causae lucrativae non concurrunt). If the same object was left to the same person by two different testators, the legatee could not claim it twice over. The property could pass once under one lucrative title; the second bequest was absorbed by the first acquisition.
Why It Matters in Research
This term appears almost exclusively in sources treating Roman law foundations of civil law systems, and in English legal literature primarily as background for understanding the civil law of succession, gifts, and unjust enrichment. Researchers encountering lucrativa causa in historical English-language sources are almost certainly reading a work that draws heavily on Roman or civilian authority — treatises on the law of Scotland, Louisiana, Quebec, or comparative legal history.
The non-concurrence principle (duae causae lucrativae non concurrunt) has practical relevance in civilian jurisdictions when tracing whether a legatee who receives the same asset under multiple testamentary instruments takes once or claims cumulatively. This rule also surfaces in the Roman law doctrine of usucapion: a possessor whose lucrativa causa was defective (for example, one who was a mala fide possessor) could not cure the defect through the passage of time in the same way a bona fide purchaser for value could.
Researchers working in the Law Mind corpus should treat lucrativa causa as a signal term. Its appearance in a text locates that text within a civilian or Roman law tradition, or marks a moment in common law scholarship when authors were engaging comparatively with Roman sources. The term does not appear in standard common law pleading or practice materials.
Historical Dictionary Support
Black's Law Dictionary (both the first and second editions) and Rapalje & Lawrence offer materially identical definitions, which reflects the term's stable meaning in the civilian tradition. All three sources correctly identify the opposition between lucrativa causa and onerosa causa, and all flag the non-concurrence principle as the operative rule of most practical significance.
Rapalje & Lawrence's entry is fragmentary as preserved — it gestures toward the connection between lucrativa causa and the position of a mala fide possessor, which is an important doctrinal link the other entries do not develop. A mala fide possessor who acquired property under a purported lucrativa causa that was defective or fictitious could not benefit from acquisitive prescription in the same manner as a good faith possessor for value. This is a meaningful gap in the Black's entries that researchers relying solely on those sources might miss.
None of the three historical dictionary sources engage with how the concept translated into modern civil law jurisdictions or how courts applying mixed or civilian law have treated the non-concurrence rule. For those purposes, the historical dictionaries are a starting point only.
Jurisdictional Note
Lucrativa causa as an operative legal concept is most relevant in jurisdictions with civilian or mixed legal traditions — Louisiana, Quebec, Scotland, South Africa, and the civil law countries of continental Europe and Latin America. In pure common law jurisdictions the concept has no direct procedural or statutory foothold, though it appears in scholarly and comparative legal literature.
Encyclopedia Cross-Reference
Property Law Encyclopedia: Personal Property — Gifts (Inter Vivos, Causa Mortis — Delivery, Intent, Acceptance)