Also known as: mental incompetence · mentally incompetents · incompetent · mental incapacity · incompetency
Written by attorneys · grounded in primary & secondary sources — see below
A condition in which a person lacks sufficient mental capacity to understand the nature and consequences of legal transactions, proceedings, or conduct. This status triggers special procedural protections in litigation and affects the validity of consent, contracts, and certain criminal liabilities. Courts assess capacity based on the individual's ability to comprehend relevant information and make rational decisions at the time of the act in question.
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Malcolm McKinley failed to appear in a contract action seeking a fixed sum of damages. The plaintiff submitted an affidavit of the amount due and requested entry of judgment by the clerk. Because McKinley had been adjudicated mentally incompetent and lacked a guardian, the clerk could not enter the judgment under the applicable rule.
Musa Mensah, the owner of a construction site, assigned an aging employee with documented cognitive lapses to operate heavy machinery near pedestrians. Mensah knew of the employee's prior misjudgments yet continued the assignment to cut costs. When the machine caused injury, Mensah faced direct negligence liability for using an instrumentality he knew posed an unreasonable risk.
Madison Meyers served as legal representative for her mentally incompetent sister in a personal-injury suit. The sister had been domiciled in Illinois at the time she became incompetent. The federal court treated Meyers as a citizen of Illinois only for purposes of determining diversity jurisdiction.
Megan Moore lured an elderly neighbor known to suffer dementia into a vehicle by misrepresenting the trip as a medical appointment. Moore confined the neighbor for several hours in an isolated location to facilitate another crime. Because the victim was incompetent, the confinement was unlawful even without force or threat.
Monica Morgan and her spouse sought dissolution of their marriage. Their adult child, Mariam Mansour, had been adjudicated mentally incompetent and required ongoing support. The court directed a portion of the marital estate into a trust to provide for the child's maintenance and welfare.
Metro Bank assigned a newly licensed associate with no supervision to handle complex commercial litigation for a major client. The associate committed ethical violations that harmed the client. The firm's partners faced discipline for failing to provide oversight that would have prevented the incompetent representation.
A clerk may not enter a default judgment for a sum certain against a defendant who has been adjudicated mentally incompetent. The plaintiff must instead apply to the court, and judgment may be entered only if the incompetent person is represented by a guardian or similar fiduciary who has appeared.
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…perfect good faith, by persons who are not considered, and in many other respects may not deserve to be considered, ignorant or incompetent, that it is rarely possible, on adequate grounds, conscientiously to stamp the misrepresentation as morally culpable; and still less could law presume to interfere with this kind of…
…this Court held: "In criminal trials, in the courts of the United States, wherever a question arises whether a confession is incompetent because not voluntary, the issue is controlled by that portion of the Fifth Amendment. . . commanding that no person shall be compelled in any criminal case to be a witness against…
…with such copies as are necessary. Service shall be made as follows: "(1) Upon an individual other than an infant or an incompetent person, by delivering a copy of the summons and of the complaint to him personally or by leaving copies thereof at his dwelling house or usual place of abode with some person of suitable…
…provided in this section, if a pregnant woman is less than 18 years of age and not emancipated, or if she has been adjudged an
…State the far lesser burden of reconsideration of the sentence alone. On the other hand, the consequences to the defendant of incompetent assistance at a capital sentencing could not, of course, be greater. Recognizing the unique seriousness of such a proceeding, we have repeatedly emphasized that " 'where discretion is…
A contract is voidable if the person lacked capacity to understand its nature and significance at the time of formation. The incompetent party or a later-appointed representative may disaffirm the contract, though liability for necessaries may still arise in quasi-contract.
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Yes. Confinement of an incompetent person is unlawful if accomplished without the consent of a parent, guardian, or other person responsible for the victim's welfare, even in the absence of force, threat, or deception.
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The legal representative of an incompetent person is deemed a citizen only of the same state as the incompetent. This rule prevents manipulation of diversity jurisdiction through appointment of out-of-state representatives.
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A defendant is incompetent if, because of mental condition, the defendant lacks a rational and factual understanding of the proceedings or lacks sufficient ability to consult with counsel with a reasonable degree of rational understanding. Due process prohibits trial of an actually incompetent defendant.
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