Definition
Per misadventure is a Latin-English term of art from old English law meaning "by mischance" or "by accident." It describes a homicide or harmful act that results not from intent, negligence, or malice, but from pure accidental misfortune. The phrase is synonymous with per infortunium — both expressions denoted an act that caused death or injury without the actor's fault, design, or criminal purpose.
In the classical common law framework, homicide per misadventure was a recognized category of excusable homicide: the killing of another person while the actor was engaged in a lawful act, with no unlawful intent, through an unforeseen accident. The paradigm case was an archer whose arrow went astray and struck a bystander, or a woodcutter whose axe-head flew off and killed a passerby. Because the act was excusable rather than justifiable, the early common law still technically required a royal pardon — the actor was not wholly free from legal consequence even though no felony had been committed.
Common Language
Modern common usage (Wiktionary): "Misadventure" means an unfortunate incident or accident; a piece of bad luck.
Historical common usage (Webster's 1913): "Misadventure" — an unlucky accident; a mishap; ill luck; misfortune.
The ordinary meaning of misadventure tracks closely to the legal one, but the gap matters in a specific way: in common English, misadventure is merely descriptive of bad luck with no legal weight. In old English law, per misadventure was a formal legal classification carrying distinct consequences — the difference between excusable homicide (which required pardon) and justifiable homicide (which did not), and both of which stood apart from felonious killing. A researcher reading historical sources must not treat the word as casual description when it appears as a legal term of classification.
Common Confusion
Per misadventure and per infortunium are used interchangeably across historical sources, including Blackstone, Coke, and the major historical dictionaries. They are functionally equivalent. However, a researcher may encounter per infortunium more frequently in strictly Latin legal texts, while per misadventure appears in sources blending Latin and English terminology. Neither term should be confused with chance-medley (homicide occurring in the heat of a sudden affray), which occupied a separate doctrinal category, or with se defendendo (killing in self-defense), which was also excusable but arose from a distinct factual posture. All three shared the consequence of requiring pardon under early English law, which makes them easy to conflate in historical court records.
Why It Matters in Research
Researchers working with historical English criminal law materials — particularly records predating the 19th-century codification of homicide — will encounter this phrase as a term of formal legal classification, not mere description. Several research traps exist.
First, the pardon requirement: because excusable homicide per misadventure technically required a royal pardon even when the actor bore no fault, archival records of pardon proceedings may feature this phrase prominently. A record showing a pardon does not mean the actor committed a crime; it may simply reflect the procedural posture of the excusable homicide framework.
Second, the doctrinal neighborhood is crowded. Historical sources use per misadventure, per infortunium, chance-medley, and se defendendo in close proximity, and the distinctions among them collapsed and shifted across centuries. Eighteenth-century treatise writers did not always draw the same lines as their predecessors.
Third, the term is essentially extinct in modern legal usage. Contemporary law has replaced the classical categories of homicide with statutory frameworks. A researcher who encounters per misadventure in a modern document is almost certainly reading a historical quotation, an academic treatise, or a comparative law source — not operative legal language.
Fourth, the Law Mind corpus connections run toward the historical foundations of tort and criminal law rather than toward modern doctrine. This term predates the negligence framework; the concept of accidental harm causing death without fault is ancestral to modern negligence doctrine, but per misadventure should not be read backward as an early statement of negligence per se or strict liability.
Historical Dictionary Support
Black's Law Dictionary (both editions) and Burrill's Law Dictionary are in complete agreement: per misadventure means "by mischance" and is synonymous with per infortunium. All three cite Blackstone's Commentaries (4 Bl. Comm. 182) as the primary authority, with Black's first edition adding a reference to Coke (9 Coke, 113a) and to 3 Bl. Comm. 142 for the phrase's connection to special damage.
The historical dictionaries are thin on doctrinal elaboration — they define the term accurately but do not explain the excusable/justifiable distinction or the pardon consequence, which a researcher needs to understand the term's legal significance. For that context, Blackstone himself remains the indispensable primary source. The dictionaries function here as signposts pointing toward Blackstone, not as self-sufficient explanations.
None of the historical dictionary entries address the term's disappearance from operative legal usage, which means a researcher relying solely on these sources could mistakenly treat per misadventure as a living legal category.
Encyclopedia Cross-Reference
The Law Mind encyclopedia entries matched to this term (Negligence Per Se, Physical Takings Per Se Rules, Defamation Per Se) share only the Latin preposition per and are not substantively related to per misadventure. No Law Mind Encyclopedia entry is a natural match for this term.