Definition
Latin. "To prove." A civil law and Latin legal term meaning to establish something as true or genuine through evidence, oath, or demonstration sufficient to satisfy a judicial tribunal. In legal usage, probare carries two related but historically distinct senses:
1. (Saxon/early law) To claim a thing as one's own; to assert ownership or right by formal declaration.
2. (Modern law Latin) To make proof; to demonstrate the truth of a fact or the validity of a legal instrument before a court or judge. The term survives primarily in derivative phrases — most prominently onus probandi (the burden of proof) and necessitas probandi (the necessity of proving) — rather than as a standalone term in contemporary pleading or procedure.
The classical maxim draws the functional meaning precisely: probare est fidem facere judici — "to prove is to convince or satisfy the judge." This formulation frames proof not as an abstract logical exercise but as a relational act directed at a specific decision-maker.
Common Confusion
The two historical senses of probare — asserting ownership (Saxon usage) and making proof (civil law usage) — point in different directions and should not be conflated. The Saxon sense resembles a claim or declaration of right; the civil law sense is evidentiary and procedural. Researchers encountering probare in early sources must determine which tradition the source is drawing on. Black's Law Dictionary acknowledges both but does not clearly flag that these are functionally distinct legal operations. Burrill's entry develops only the evidentiary sense and is the more reliable guide for understanding probare in probate and procedure contexts.
Why It Matters in Research
Probare is not a term researchers will encounter in modern statutory text or contemporary case law; it belongs to the Latin substructure of legal doctrine and appears almost exclusively in maxims, civil law treatises, and historical sources. Its primary research value is as a root term: understanding probare unlocks a cluster of derivative terms — probandi, probatum, probata, probandum — that appear regularly in historical legal writing and that carry precise procedural meanings.
The phrase onus probandi, still cited in modern evidence scholarship, descends directly from this root. Researchers working in historical evidence law, Roman law influence on common law procedure, or the development of burdens of proof will encounter probare and its derivatives repeatedly. Burrill's maxim — necessitas probandi incumbit illi qui agit ("the necessity of proving lies upon him who sues") — is a foundational statement of the plaintiff's burden, and tracing it requires comfort with the probare family.
A secondary trap: probate (the legal process for validating wills) shares this Latin root and preserves the "making proof" sense in its name — probate courts were originally venues where a will was proved, i.e., its authenticity demonstrated before a judge. Researchers moving between probate history and evidence history should recognize probare as the conceptual bridge.
Historical Dictionary Support
The four source dictionaries agree on the core translation ("to prove") but differ in depth and emphasis. Black's (both editions) offers a compressed entry that does the minimum: it acknowledges the Saxon ownership-claim sense via Jacob's Law Dictionary and pivots to onus probandi for the modern sense. Neither edition develops the term independently.
Anderson's treats probare as a pure translation entry and redirects researchers immediately to derivative terms — factum probandum and onus probandi — without explaining the term itself. This is efficient but unhelpful for researchers who need context.
Burrill's is the most substantively useful entry. It supplies the maxim necessitas probandi incumbit illi qui agit with a citation to the Institutes (Inst. 2.20.4), grounding probare in Roman civil law authority. It also supplies the definitional maxim probare est fidem facere judici — "to prove is to convince or satisfy the judge" — attributed to a treatise on presumptive proof, and begins an entry on probate procedure that connects the evidentiary meaning to the English practice of proving wills either in common form (by executor's oath) or per testes (by witnesses). Burrill thus draws the connection between the abstract Latin term and its concrete procedural applications more effectively than the other sources.
What none of the source dictionaries adequately addresses is the Roman law lineage: probare in classical Latin and in the Corpus Juris Civilis carried the sense of approval and demonstration simultaneously — probatio meant both "testing" and "approval." This deeper meaning helps explain why the same root produces both probate (approval of a will) and probative (tending to prove), two words modern lawyers treat as unrelated.
Encyclopedia Cross-Reference
See Law Mind Encyclopedia: Burden of Proof; Probate and Will Proof; Latin Maxims in Common Law Evidence