Definition
En bonne foy is a Law French phrase meaning "in good faith." It signifies conduct undertaken honestly, sincerely, and without intent to deceive or defraud. In legal usage, the phrase functions as an adverbial qualifier describing the manner in which an act, agreement, or obligation is to be performed — that is, with genuine intention and without concealment of material facts.
The phrase is the historical antecedent of the modern doctrine of good faith as it appears across contract law, property law, commercial law, and equity. Where it appears in early English legal records, it signals that a party's claim, plea, or transaction is grounded in honest dealing rather than artifice.
Common Language
Modern common usage (Wiktionary): "Good faith" — sincerity of intention; honesty of purpose; absence of any intent to defraud or deceive.
Historical common usage (Webster's 1913): "Good faith" — honesty of intention; absence of design to defraud.
The common meaning tracks the legal meaning closely here, but the gap lies in register and context: in ordinary usage, "good faith" is a loose moral descriptor. In historical legal texts, en bonne foy was a term of art with procedural and substantive consequences — invoking it in a pleading or instrument was not merely a statement of character but a legally significant representation about the basis of a claim or transaction.
Common Confusion
EN BONNE FOY vs. BONA FIDE / BONA FIDES: These terms are functional equivalents — en bonne foy is the Law French form, bona fide and bona fides the Latin. Researchers may encounter either in historical sources depending on the period and the court. Earlier Year Book materials tend toward Law French; later common law and equity writings increasingly favor the Latin. Neither form carries a meaningfully different legal content, but they may index to different documentary traditions within the corpus.
Why It Matters in Research
This term is almost exclusively a Year Book and early medieval law French artifact. Researchers are unlikely to encounter en bonne foy in sources after the seventeenth century except as a historical quotation or citation to earlier authority. By the time English legal writing had transitioned away from Law French — formally abolished for pleadings by statute in the eighteenth century — the Latin bona fide and the English "good faith" had fully displaced it.
The practical research trap is terminological fragmentation: the same underlying doctrine appears under at least three linguistic forms across the corpus (en bonne foy, bona fide, good faith), and searching any one form alone will produce an incomplete picture of how the concept developed. A researcher tracing the history of the good faith doctrine through the corpus must follow all three threads.
Burrill's citation to the Year Books (T. 4 Edw. II) anchors this as a thirteenth- to fourteenth-century usage. Researchers working in that period should expect Law French to dominate; the shift toward Latin forms in legal instruments and pleadings accelerates through the fifteenth and sixteenth centuries.
En bonne foy also appears in property and conveyancing contexts, where honest dealing between grantor and grantee had direct consequences for the validity of a transfer. Its presence in a historical instrument may signal that the parties were attempting to establish the absence of fraud or collusion — relevant when reading instruments in the context of fraudulent conveyance doctrine or bona fide purchaser analysis.
Historical Dictionary Support
Burrill's Law Dictionary provides the core entry: "L. Fr. In good faith" with a citation to the Year Books, Term 4 Edward II, page 107. The entry is characteristically spare — Burrill identifies the linguistic origin (Law French), provides the translation, and pins the usage to a specific early source. Nothing in the entry suggests substantive divergence from the bona fide/good faith cluster; Burrill treats the terms as equivalent in meaning.
What historical dictionaries largely omit is any account of the doctrine's downstream development. The connection between this Law French phrase and the fully elaborated modern good faith doctrines in contract, commercial law, and equity is a story told elsewhere — in treatises on equity, in commentary on the Uniform Commercial Code, and in comparative legal scholarship. The dictionary entry is a linguistic marker, not a conceptual history.
Encyclopedia Cross-Reference
See Law Mind Encyclopedia: GOOD FAITH; BONA FIDE PURCHASER; FRAUDULENT CONVEYANCE