Definition
Infancy, in law, is the status of a person who has not yet reached the age of legal majority — at common law, twenty-one years. The term is used interchangeably with minority and nonage. Depending on context, infancy may describe:
1. AGE STATUS: The bare fact of being under the age of legal majority, without reference to any particular legal consequence.
2. CONTRACTUAL INCAPACITY: The bundle of disabilities attached to non-age, most significantly the general rule that contracts entered into by an infant are voidable at the infant's election.
3. CRIMINAL IRRESPONSIBILITY: The doctrine that children below a specified age are presumed incapable of forming criminal intent (doli incapax), and therefore cannot be held criminally liable. At common law, children under seven were conclusively presumed incapable; those between seven and fourteen were presumed incapable but the presumption could be rebutted; those fourteen and over were treated as adults.
The legal usage of infancy is not limited to very young children. A person of twenty years and eleven months is legally an infant; a six-month-old and a twenty-year-old are both infants for purposes of contractual capacity.
Common Language
Modern common usage (Wiktionary): The earliest period of childhood — a baby or very young child who crawls rather than walks; also, an early stage in the development of anything; also, as a legal sense, the state of being a minor.
Historical common usage (Webster's 1913): The first part of life, early childhood; the first age of anything; and also, explicitly, the state of being under twenty-one years of age.
Webster's 1913 captures both meanings, which is unusual: the common meaning refers to babies and toddlers, while the legal meaning encompasses anyone under twenty-one. A researcher encountering "infancy" in a historical legal document should not assume it describes a young child — it may describe a nineteen-year-old. The Wiktionary definition, to its credit, lists the legal sense separately, but the gap between the popular and legal meanings remains large enough to cause misreading.
Common Confusion
INFANCY, MINORITY, AND NONAGE
Infancy, minority, and nonage are used interchangeably in most legal sources and all mean the same thing: the state of being under the age of legal majority. Infancy is the older common-law term; minority became the preferred term in most modern statutes. Nonage is largely a historical and civil-law term. None of these terms, in legal usage, is limited to very young children. A researcher should treat them as synonyms unless a source draws an explicit distinction.
Separately, the civil law recognized infancy (infantia) as only one stage of minority — roughly, birth to age seven. That technical civil-law subdivision should not be confused with the common-law doctrine, which uses infancy to mean the entire period of minority through age twenty-one.
Core Elements
The legal doctrine of infancy operates differently across its three main contexts:
CONTRACTUAL INCAPACITY
— An infant's contracts are generally voidable, not void: the infant may elect to disaffirm or ratify upon reaching majority.
— Contracts for necessaries (food, shelter, clothing, medical care) are a recognized exception and may be enforced against the infant.
— Ratification upon majority, whether express or implied by conduct, extinguishes the right to disaffirm.
CRIMINAL IRRESPONSIBILITY (Common Law)
— Under age seven: conclusive presumption of incapacity; no criminal liability.
— Ages seven to fourteen: rebuttable presumption of incapacity; prosecution must show the child understood the wrongfulness of the act.
— Age fourteen and above: presumed capable; treated as an adult at common law.
Recognized Forms
/SUBTYPES
CIVIL LAW SUBDIVISION: The civil law divided minority into stages — infantia (birth to approximately seven years), the period of proximate infancy, and full minority. The common law did not adopt this subdivision for civil purposes, though it used a similar framework for criminal liability.
TENDER YEARS: Courts and statutes sometimes distinguished very young children for specific purposes (custody presumptions, evidentiary competency) without departing from the general common-law rule on majority.
Why It Matters in Research
Historical legal sources use infancy without qualification to mean any person under twenty-one. A researcher reading a nineteenth-century contract case who encounters "the plaintiff was an infant" should not visualize a toddler — the plaintiff may have been a young adult. This is one of the most common misreadings a modern reader can make.
The age of majority has shifted significantly. The common-law rule was twenty-one. Most American jurisdictions lowered it to eighteen following the Twenty-Sixth Amendment (1971) and a wave of state statutory reform in the 1970s. Researchers working with sources from before that period should assume twenty-one as the baseline unless the source specifies otherwise.
The criminal incapacity doctrine is the area of greatest doctrinal complexity and change. Historical sources apply the three-tier common-law framework (under seven, seven to fourteen, fourteen and above). Modern jurisdictions have largely codified and modified these rules through juvenile court statutes, which created a parallel system rather than simply adjusting age thresholds. Research in criminal law sources spanning the late nineteenth to mid-twentieth centuries will encounter the transition from the common-law framework to the juvenile court model, and the two systems operate on different logics. The encyclopedia entry on Age of Criminal Responsibility addresses this transition in detail.
Contractual incapacity doctrine generated extensive case law, and researchers should be attentive to the necessaries exception, which was litigated frequently. The boundary of what counted as a necessary was contested — courts disagreed on whether education, employment contracts, and insurance qualified.
The civil law subdivision of infancy into stages (particularly infantia through age seven) appears in some American sources that drew on civil law, especially in Louisiana and in scholarly treatises. Do not assume this subdivision applied in common-law jurisdictions.
Historical Dictionary Support
The shelf sources are in close agreement on the core definition. Bouvier, Burrill, and both editions of Black's all define infancy as the state of being under the age of twenty-one — treating it as synonymous with minority and nonage. Burrill adds the most doctrinal texture, explicitly noting that the civil law term infantia designated only one stage of minority reaching to age seven, and distinguishing that usage from the common-law term. This is a useful clarification that Black's omits.
Black's (both editions) goes further than Bouvier and Burrill by identifying the three distinct registers in which infancy operates — age status, contractual disability, and relational status — signaling that the term's meaning depends on context. The second edition adds a Michigan case citation for this proposition. Rapalje & Lawrence's entry appears incomplete in available form, contributing only a fragment.
None of the historical dictionaries addresses the criminal incapacity doctrine in depth under this headword; that doctrine is typically developed under the heading Infant or under criminal law entries. Researchers should follow the cross-reference to Infant in all shelf sources for fuller treatment of the criminal capacity rules and the capacity to hold property or sue.
Jurisdictional Note
The age of majority in American jurisdictions is now generally eighteen by statute, following reform in the 1970s. Federal law and some state laws set different ages for specific purposes (alcohol, voting, contracts for particular goods). England similarly moved to eighteen under the Family Law Reform Act 1969. Louisiana's civil law tradition preserved elements of the civil-law subdivision of minority longer than other states. Researchers working across jurisdictions or time periods should always confirm the controlling age threshold for the specific context.
Encyclopedia Cross-Reference
Infancy — Age of Criminal Responsibility (The Law Mind Criminal Law Encyclopedia)