Also known as: capacity defence · capacity defenses · capacity defences · incapacity defense · lack of capacity
Written by attorneys · grounded in primary & secondary sources — see below
A defense asserting that a party cannot be held legally responsible for an act or bound by a transaction due to insufficient mental or legal ability arising from age, mental illness, or similar condition.
Select any source to read its text and confirm it supports the definition.
Claire Campbell, age seventeen, purchased a used car from Cardinal Insurance for $8,000 and drove it for three months before returning it and demanding her money back. She disaffirmed the contract on the ground of infancy. The court ordered Cardinal Insurance to refund the full purchase price even though the car had depreciated in value during her use.
Charles Cunningham faced a death sentence after conviction for murder. His trial counsel failed to review prison records showing long-term mental illness and low cognitive functioning. Post-conviction review established that this evidence would have supported a capacity defense at sentencing and altered the outcome.
Cassandra Cooper shot a police officer during a delusional episode. At trial she offered expert testimony on her mental disease to negate mens rea. The court limited the evidence to the traditional insanity test and excluded broader capacity arguments, resulting in conviction.
Caitlin Crowley sued Compass Logistics in State A for breach of a contract she later claimed she lacked capacity to sign. After transfer to State B, the court applied State B law to determine whether her capacity defense could still be raised in the new forum.
Clifford Cox, diagnosed with schizophrenia, insisted on representing himself at trial. The court found he lacked the mental capacity to conduct his own defense despite being competent to stand trial and appointed counsel over his objection.
Camila Cervantes, age seventeen at the time of the offense, received a death sentence. The court held that her age rendered her categorically ineligible for capital punishment because juveniles lack the full moral capacity required for the ultimate penalty.
The party must prove lack of capacity at the time of contracting and that the contract has been avoided. Once avoidance occurs, the party may recover benefits conferred through part performance or reliance.
…on the merits. The only defense witness was a Dr. Sheuerman who was called by Chapman in an effort to establish a defense of lack of capacity to form the requisite intent because of "disassociative reaction." The prosecutor's comment on petitioners' failure to explain away or challenge the evidence presented against them was…