Definition
Latin: "In this behalf; on this part or side." A Latin phrase used in legal writing and pleading to indicate that a statement, argument, or action pertains to or is made on behalf of a particular party, or is limited to the specific matter at hand. The phrase functions as a localizing or limiting expression — it signals that what follows applies to this particular side, this particular issue, or this particular aspect of the proceeding, rather than to the matter generally.
The phrase appears most frequently in older formal pleadings, writs, and judicial orders where precision about which party or which part of a controversy is being addressed was critical to the record.
Common Confusion
IN HAC PARTE is sometimes confused with EX PARTE, a far more common Latin phrase in modern legal usage. The two are distinct. EX PARTE means "from one side only" and carries substantive procedural significance — it describes proceedings or orders made at the request of and for the benefit of one party without notice to the opposing party. IN HAC PARTE, by contrast, is not a procedural posture; it is a rhetorical or drafting locution meaning simply "in this respect" or "on this point." A court issuing an ex parte order is acting within a recognized procedural category. A writer using in hac parte is merely specifying that a statement applies to a particular side or aspect of the matter. Conflating the two can produce significant misreadings in historical pleadings and judicial opinions.
Why It Matters in Research
Researchers encountering IN HAC PARTE in historical sources should treat it as a localizing phrase rather than a term of art with independent legal significance. Its primary function is grammatical and rhetorical — it limits the scope of what follows in a sentence or paragraph. This means its meaning can only be captured in context; reading it in isolation produces nothing useful.
Several practical traps arise in corpus research:
First, the phrase appears in close proximity to other Latin maxims in older digests and abridgments, sometimes in transitional passages where it links one maxim to the next rather than standing alone as a defined concept. Black's, Burrill's, and Bouvier's all treat it briefly as a translation entry, not as an independent doctrine.
Second, the variant spelling IN HÆC PARTE (using the æ ligature) appears throughout pre-twentieth-century sources. Corpus searches that do not account for this orthographic variation will miss a significant portion of historical appearances. Note also IN HÆC VERBA ("in these words"), a closely related phrase appearing immediately adjacent to IN HAC PARTE in multiple historical dictionaries — the two are distinct, and their proximity in alphabetically arranged sources has led to conflation in index and digest citations.
Third, because the phrase is used across virtually every subject area of law (property, pleading, equity, criminal law), it does not serve as a reliable topical marker in full-text corpus searching. Its presence in a document tells a researcher very little about subject matter.
Fourth, the Rapalje & Lawrence entry is notable for pivoting immediately from IN HAC PARTE into a discussion of in forma pauperis procedure under 23 Hen. VIII, c. 15 — a quirk of alphabetical arrangement, not substantive connection. Researchers using that source should not infer any relationship between the phrase and poor-litigant procedure.
Historical Dictionary Support
All four source dictionaries are in agreement: IN HAC PARTE means "in this behalf" or "on this part or side." There is no meaningful divergence among the sources on the core translation. Burrill's cites Reg. Orig. 25 (Registrum Omnium Brevium) as a source, placing the phrase in the tradition of writ-pleading practice. Bouvier's offers the most complete translation — "in this behalf; on this part or side" — which captures both the personal (party-referencing) and topical (issue-referencing) uses of the phrase. Black's and Rapalje & Lawrence add IN HÆC VERBA immediately after, confirming the alphabetical proximity that can cause confusion in research.
None of the historical dictionaries offers extended discussion of the phrase's use in practice, which reflects its status as a common connective rather than a substantive legal category. Modern legal dictionaries largely omit the phrase entirely, consistent with the decline of Latin pleading.
Jurisdictional Note
IN HAC PARTE carries no jurisdiction-specific meaning. Its content varies only with context and era, not with geography. It appears in English, American, and other common law sources wherever Latin pleading conventions were followed.
Encyclopedia Cross-Reference
The phrase has no direct substantive connection to any Law Mind Encyclopedia entry. Researchers consulting this entry for guidance on related procedural concepts may find the following of incidental interest:
— Family Law Encyclopedia, family_171: Domestic Violence — Emergency / Ex Parte Orders of Protection (for the procedurally significant concept of ex parte, which is frequently confused with in hac parte)