IRREGULARITY

Definition

A departure from prescribed procedural rules or established court practice in the conduct of a legal proceeding. Irregularity is the technical term for defects in practical proceedings — it covers both the failure to do something required for the orderly conduct of a suit and the doing of something in the wrong time or in an improper manner. Critically, irregularity is distinguished from illegality or nullity: an irregular act is not necessarily void. The defect is in the manner or timing of a procedural step, not in the authority to take it at all. A party who suffers an irregularity must typically object promptly; failure to do so is treated as waiver. An act may be irregular and yet remain valid unless and until set aside on motion.

Common Language

Modern common usage (Wiktionary): An instance of being irregular; a violation of rules; something not regular or ordinary; also used colloquially for irregular bowel movement. Historical common usage (Webster's 1913): The state or quality of being irregular; that which is irregular. The everyday sense of irregularity suggests any deviation from a norm, large or small, with no implication about consequences. The legal sense is narrower and more technical: it refers specifically to procedural missteps in the conduct of litigation, and carries the important implication that the defect is curable or waivable rather than fatal. Researchers must resist reading modern or lay connotations — which suggest the act is simply wrong — back into a legal context where irregularity is a term of art meaning something less than invalidity.

Common Confusion

Irregularity vs. Nullity vs. Illegality: These three concepts occupy different positions on a spectrum of procedural defect. An irregularity is a departure from prescribed practice that does not automatically void the act — it must be challenged by motion. A nullity is an act so fundamentally defective that it is void from the outset and confers no legal effect. An illegality involves a violation of substantive law, not merely procedural form. Historical sources frequently use these terms inconsistently, and researchers working in older reports should not assume that a court's use of "irregular" carries modern doctrinal precision.

Why It Matters in Research

The most important navigational point for corpus researchers is the consequences distinction. Historical courts and commentators used "irregularity" as a term of art to mark the boundary between curable procedural defect and fatal invalidity — but they did not always draw that line in the same place. What one era or jurisdiction treated as a mere irregularity, another might treat as a jurisdictional defect requiring dismissal. This means that tracking outcomes in cases involving procedural defects requires attention to how the court characterized the defect, not merely whether it found one. The waiver trap is significant. Because an irregularity must be objected to promptly — before the complaining party takes any further step in the proceeding — older reports frequently turn on whether the objection came in time. Researchers looking for substantive rulings may find that cases they expect to address a procedural question are actually decided entirely on waiver grounds. The term also appears frequently in election law and administrative law contexts, where "irregularity" describes departures from statutory procedure that may or may not affect the validity of an election or agency action. These uses are related but not identical to the core procedural definition, and the consequences analysis differs by context. Bouvier's observation that a party must except to an irregularity before proceeding further is a persistent feature of Anglo-American practice and reappears across jurisdictions and time periods. It is one of the most reliable doctrinal anchors when tracing the term through the corpus.

Historical Dictionary Support

The historical dictionaries align closely on the core definition. Black's (both editions) and Burrill's all draw on the same underlying source — Tidd's Practice — and use nearly identical language: irregularity is the want of adherence to a prescribed rule or mode of proceeding, consisting in omission of a required act or performance of a required act at the wrong time or in an improper manner. This uniformity reflects the term's deep roots in English common law practice. Bouvier adds the most substantively useful gloss: irregularity is usually applied to informality that does not render the act invalid from the outset (he illustrates with the example of an irregular distress for rent, which is not illegal ab initio). This is the sharpest statement in the historical sources of the curable-not-void principle, and it is the most useful passage for researchers trying to understand why courts distinguish irregularity from nullity. Burrill's Latin framing — departure from regula, non-observance of rule — underscores that the concept is fundamentally about procedural form, not substantive right. What the historical sources largely omit is any systematic treatment of when an irregularity ripens into something more serious, and how courts should classify borderline cases. That doctrinal development is worked out in case law rather than the dictionaries, and researchers should not expect the dictionary definitions alone to resolve hard classification questions. Rapalje & Lawrence's entry is not responsive to this term and provides no useful content.

Jurisdictional Note

The core distinction between irregularity and nullity is common across common law jurisdictions, but the procedural consequences — including the timing rules for objection and the availability of cure — vary by jurisdiction and are frequently codified in rules of civil procedure. Researchers should consult applicable rules of court rather than relying on general common law formulations when working in a specific jurisdiction.

Related Terms