Also known as: cognitive capacities · mental capacity · mental competency
Written by attorneys · grounded in primary & secondary sources — see below
The mental ability to understand the nature and consequences of a transaction or action. This ability is assessed at the time the relevant act occurs and determines whether the resulting transfer, agreement, or conduct carries legal effect.
Carmen Choi, recovering from surgery and taking strong pain medication, signed an irrevocable assignment transferring her entire investment portfolio to a speculative hedge fund. Her spouse had no independent income and pending long-term care insurance. The assignment is invalid because Choi lacked the cognitive capacity to understand the gift's impact on her future financial security and that of her dependent spouse.
Trevor spent the afternoon drinking hard cider and smoking marijuana. During the marriage ceremony he laughed inappropriately and needed repeated prompting to recite his lines. The marriage is invalid because Trevor lacked the cognitive capacity at the time of the ceremony to understand his actions and agree to them.
Select any source to read its text and confirm it supports the definition.
Eighty-eight-year-old Eric, residing in assisted living and relying on rental income, executed an irrevocable deed transferring an income-producing building to Silver Housing. He occasionally confused family members and tenants. The deed is invalid because Eric lacked the cognitive capacity both to make or revoke a will and to understand the gift's effect on his future financial security.
Christian Coleman was charged with murder after shooting a neighbor. At trial he presented evidence of long-standing delusions that prevented him from comprehending the wrongfulness of his conduct. The jury must decide whether Coleman possessed sufficient cognitive capacity to form the criminal intent required for murder.
Connor Clark, sentenced to death, began claiming he owned the prisons and could control the governor through mind waves. Psychiatrists concluded he had no understanding of why he was to be executed. The court must determine whether Clark retains the cognitive capacity to comprehend the connection between his crime and the punishment.
Christopher Collins was found inside a residence after a reported break-in. He had a documented history of mental illness that produced delusions at the time of entry. The court must decide whether Collins's cognitive capacity was so impaired that he could not appreciate the criminality of his conduct.
Cognitive capacity asks whether mental illness left the defendant unable to understand what he was doing. Moral capacity asks whether the illness rendered him unable to understand that his action was wrong. Either deficiency can support an insanity acquittal.
Capacity is determined at the precise moment of the marriage ceremony. Intoxication or drug use at that instant can prevent the parties from understanding their actions and agreeing to them.
Supporting sources
The donor must possess the mental capacity needed to make or revoke a will and must also understand the gift's effect on the donor's future financial security and on anyone dependent on the donor.
Supporting sources
No. The party must prove inability at the time of contracting to understand the nature and consequences of the transaction.
…S. 307 (1976); religious or political affiliation, Karcher v. Daggett , 462 U. S. 725, 748 (1983) (STEVENS, J., concurring); mental capacity, Cleburne v. Cleburne Living Center, Inc. , 473 U. S. 432 (1985); number of children, Dandridge v. Williams , 397 U. S. 471 (1970); living arrangements, Department of Agriculture v.…