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10.4 Capacity

Learning Objectives

  1. Understand that infants may avoid their contracts, with limitations.
  2. Understand that insane or intoxicated people may avoid their contracts, with limitations.
  3. Understand the extent to which contracts made by mentally ill persons are voidable, void, or effectively enforceable.
  4. Recognize that contracts made by intoxicated persons may be voidable.

A contract is a meeting of minds. If someone lacks mental capacity to understand what he is assenting to—or that he is assenting to anything—it is unreasonable to hold him to the consequences of his act. At common law there are various classes of people who are presumed to lack the requisite capacity. These include infants (minors), the mentally ill, and the intoxicated.

Minors (or “Infants”)

The General Rule

The general rule is this: minorsBasically synonymous with infant: a young person who may avoid contracts on that account. (or more legalistically “infantsA person who has not reached the age of majority and who may (usually) avoid contracts on that account.”) are in most states persons younger than seventeen years old; they can avoid their contracts, up to and within a reasonable time after reaching majority, subject to some exceptions and limitations. The rationale here is that infants do not stand on an equal footing with adults, and it is unfair to require them to abide by contracts made when they have immature judgment.

The words minor and infant are mostly synonymous, but not exactly, necessarily. In a state where the legal age to drink alcohol is twenty-one, a twenty-year-old would be a minor, but not an infant, because infancy is under eighteen. A seventeen-year-old may avoid contracts (usually), but an eighteen-year-old, while legally bound to his contracts, cannot legally drink alcohol. Strictly speaking, the better term for one who may avoid his contracts is infant, even though, of course, in normal speaking we think of an infant as a baby.

The age of majorityWhen a person is old enough to make his or her contracts unavoidable on account of age. (when a person is no longer an infant or a minor) was lowered in all states except Mississippi during the 1970s (to correspond to the Twenty-Sixth Amendment, ratified in 1971, guaranteeing the right to vote at eighteen) from twenty-one to either eighteen or nineteen. Legal rights for those under twenty-one remain ambiguous, however. Although eighteen-year-olds may assent to binding contracts, not all creditors and landlords believe it, and they may require parents to cosign. For those under twenty-one, there are also legal impediments to holding certain kinds of jobs, signing certain kinds of contracts, marrying, leaving home, and drinking alcohol. There is as yet no uniform set of rules.

The exact day on which the disability of minority vanishes also varies. The old common-law rule put it on the day before the twenty-first birthday. Many states have changed this rule so that majority commences on the day of the eighteenth birthday.

An infant’s contract is voidable, not void. An infant wishing to avoid the contract need do nothing positive to disaffirm. The defense of infancy to a lawsuit is sufficient; although the adult cannot enforce the contract, the infant can (which is why it is said to be voidable, not void).

Exceptions and Complications

There are exceptions and complications here. We call out six of them.


First, as an exception to the general rule, infants are generally liable for the reasonable cost of necessities (for the reason that denying them the right to contract for necessities would harm them, not protect them). At common law, a necessity was defined as food, medicine, clothing, or shelter. In recent years, however, the courts have expanded the concept, so that in many states today, necessities include property and services that will enable the infant to earn a living and to provide for those dependent on him. If the contract is executory, the infant can simply disaffirm. If the contract has been executed, however, the infant must face more onerous consequences. Although he will not be required to perform under the contract, he will be liable under a theory of “quasi-contract” for the reasonable value of the necessity. In Gastonia Personnel Corp. v. Rogers, an emancipated infant, nineteen years old (before the age of minority was reduced), needed employment; he contracted with a personnel company to find him a job, for which it would charge him a fee.Gastonia Personnel Corp. v. Rogers, 172 S.E.2d 19 (N.C. 1970). The company did find him a job, and when he attempted to disaffirm his liability for payment on the grounds of infancy, the North Carolina court ruled against him, holding that the concepts of necessities “should be enlarged to include such…services as are reasonable and necessary to enable the infant to earn the money required to provide the necessities of life for himself” and his dependents.

Nonvoidable Contracts

Second, state statutes variously prohibit disaffirmation for such contracts as insurance, education or medical care, bonding agreements, stocks, or bank accounts. In addition, an infant will lose her power to avoid the contract if the rights of third parties intervene. Roberta, an infant, sells a car to Oswald; Oswald, in turn, shortly thereafter sells it to Byers, who knows nothing of Roberta. May Roberta—still an infant—recover it from Byers? No: the rights of the third party have intervened. To allow the infant seller recovery in this situation would undermine faith in commercial transactions.

Misrepresentation of Age

A third exception involves misrepresentation of age. Certainly, that the adult reasonably believed the infant was an adult is of no consequence in a contract suit. In many states, an infant may misrepresent his age and disaffirm in accordance with the general rule. But it depends. If an infant affirmatively lies about his age, the trend is to deny disaffirmation. A Michigan statute, for instance, prohibits an infant from disaffirming if he has signed a “separate instrument containing only the statement of age, date of signing and the signature.” And some states estop him from claiming to be an infant even if he less expressly falsely represented himself as an adult. Estoppel is a refusal by the courts on equitable grounds to allow a person to escape liability on an otherwise valid defense; unless the infant can return the consideration, the contract will be enforced. It is a question of fact how far a nonexpress (an implied) misrepresentation will be allowed to go before it is considered so clearly misleading as to range into the prohibited area. Some states hold the infant liable for damages for the tort of misrepresentation, but others do not. As William Prosser, the noted torts scholar, said of cases paying no attention to an infant’s lying about his age, “The effect of the decisions refusing to recognize tort liability for misrepresentation is to create a privileged class of liars who are a great trouble to the business world.”William L. Prosser, Handbook of the Law of Torts, 4th ed. (St. Paul, MN: West, 1971), 999.


Fourth, when the infant becomes an adult, she has two choices: she may ratify the contract or disaffirm it. She may ratify explicitly; no further consideration is necessary. She may also do so by implication—for instance, by continuing to make payments or retaining goods for an unreasonable period of time. If the child has not disaffirmed the contract while still an infant, she may do so within a reasonable time after reaching majority; what is a “reasonable time” depends on the circumstances.

Duty to Return Consideration Received

Fifth, in most cases of disavowal, the infant’s only obligation is to return the goods (if he still has them) or repay the consideration (unless it has been dissipated); he does not have to account for what he wasted, consumed, or damaged during the contract. But since the age of majority has been lowered to eighteen or nineteen, when most young people have graduated from high school, some courts require, if appropriate to avoid injustice to the adult, that the infant account for what he got. (In Dodson v. Shrader, the supreme court of Tennessee held that an infant would—if the contract was fair—have to pay for the pickup truck he bought and wrecked.)Dodson v. Shrader, 824 S.W.2d 545 (Tenn. 1992).

Tort Connected with a Contract

Sixth, the general rule is that infants are liable for their torts (e.g., assault, trespass, nuisance, negligence) unless the tort suit is only an indirect method of enforcing a contract. Henry, age seventeen, holds himself out to be a competent mechanic. He is paid $500 to overhaul Baker’s engine, but he does a careless job and the engine is seriously damaged. He offers to return the $500 but disaffirms any further contractual liability. Can Baker sue him for his negligence, a tort? No, because such a suit would be to enforce the contract.

Persons Who Are Mentally Ill or Intoxicated

Mentally Ill Persons

The general rule is that a contract made by person who is mentally ill is voidable by the person when she regains her sanity, or, as appropriate, by a guardian. If, though, a guardian has been legally appointed for a person who is mentally ill, any contract made by the mentally ill person is void, but may nevertheless be ratified by the ward (the incompetent person who is under a guardianship) upon regaining sanity or by the guardian.Restatement (Second) of Contracts, Section 13.

However, if the contract was for a necessity, the other party may have a valid claim against the estate of the one who is mentally ill in order to prevent unjust enrichment. In other cases, whether a court will enforce a contract made with a person who is mentally ill depends on the circumstances. Only if the mental illness impairs the competence of the person in the particular transaction can the contract be avoided; the test is whether the person understood the nature of the business at hand. Upon avoidance, the mentally ill person must return any property in her possession. And if the contract was fair and the other party had no knowledge of the mental illness, the court has the power to order other relief.

Intoxicated Persons

If a person is so drunk that he has no awareness of his acts, and if the other person knows this, there is no contract. The intoxicated person is obligated to refund the consideration to the other party unless he dissipated it during his drunkenness. If the other person is unaware of his intoxicated state, however, an offer or acceptance of fair terms manifesting assent is binding.

If a person is only partially inebriated and has some understanding of his actions, “avoidance depends on a showing that the other party induced the drunkenness or that the consideration was inadequate or that the transaction departed from the normal pattern of similar transactions; if the particular transaction is one which a reasonably competent person might have made, it cannot be avoided even though entirely executory.”Restatement (Second) of Contracts, Section 16(b). A person who was intoxicated at the time he made the contract may nevertheless subsequently ratify it. Thus where Mervin Hyland, several times involuntarily committed for alcoholism, executed a promissory note in an alcoholic stupor but later, while sober, paid the interest on the past-due note, he was denied the defense of intoxication; the court said he had ratified his contract.First State Bank of Sinai v. Hyland, 399 N.W.2d 894 (S.D. 1987). In any event, intoxicated is a disfavored defense on public policy grounds.

Key Takeaway

Infants may generally disaffirm their contracts up to majority and within a reasonable time afterward, but the rule is subject to some exceptions and complications: necessities, contracts made nonvoidable by statute, misrepresentation of age, extent of duty to return consideration, ratification, and a tort connected with the contract are among these exceptions.

Contracts made by insane or intoxicated people are voidable when the person regains competency. A contract made by a person under guardianship is void, but the estate will be liable for necessities. A contract made while insane or intoxicated may be ratified.


  1. Ivar, an infant, bought a used car—not a necessity—for $9,500. Seller took advantage of Ivar’s infancy: the car was really worth only $5,500. Can Ivar keep the car but disclaim liability for the $4,000 difference?
  2. If Ivar bought the car and it was a necessity, could he disclaim liability for the $4,000?
  3. Alice Ace found her adult son’s Christmas stocking; Mrs. Ace herself had made it fifty years before. It was considerably deteriorated. Isabel, sixteen, handy with knitting, agreed to reknit it for $100, which Mrs. Ace paid in advance. Isabel, regrettably, lost the stocking. She returned the $100 to Mrs. Ace, who was very upset. May Mrs. Ace now sue Isabel for the loss of the stocking (conversion) and emotional distress?
  4. Why is voluntary intoxication a disfavored defense?