Which defense asserts that the defendant was unable to understand the nature or quality of the act, or to know right from wrong, at the time of the offense?

• A. Insanity
• B. Diminished Capacity
• C. Temporary Insanity
• D. Mental Incapacity

Answer: (A)

The insanity defense asserts that, due to a mental disease or defect, the person could not understand the nature or quality of the act or know that it was wrong at the time of the offense. This aligns with the test in many jurisdictions (the M'Naghten standard), which focuses on cognitive awareness and moral understanding at the moment of the act. If that impairment prevents appreciating what one is doing or recognizing its wrongfulness, the defendant can be found not criminally responsible by reason of insanity.

Diminished capacity differs in that it aims to reduce liability by eliminating or reducing specific intent, not by negating the ability to know right from wrong. Temporary insanity is a form of insanity that applies to a limited period, but the general insanity defense is the broader fit for the described inability to understand the act or its wrongfulness. Mental incapacity is a broader term that may cover various cognitive impairments and is not the precise articulation of the right-from-wrong understanding described here.