Legal Definitions - American Law Institute test

The American Law Institute (ALI) test, also known as the Substantial Capacity Test, is a legal standard used in some jurisdictions to determine if a person is not criminally responsible for their actions due to mental illness. Developed by the American Law Institute, this test focuses on whether a defendant, because of a mental disease or defect, lacked the significant ability to either understand that their conduct was wrong or to control their behavior to comply with the law. Unlike older, stricter insanity tests, the ALI test acknowledges that mental illness might impair a person's capacities without completely eliminating them.

To be found not criminally responsible under the ALI test, a defendant must demonstrate that, as a result of a mental disease or defect, they lacked:

• Substantial capacity to appreciate the criminality (wrongfulness) of their conduct: This means they couldn't understand that what they were doing was against the law or morally wrong.
• Substantial capacity to conform their conduct to the requirements of the law: This means they knew their actions were wrong but were unable to stop themselves due to their mental condition.

Here are some examples illustrating the application of the American Law Institute test:

• Example 1 (Appreciate Wrongfulness): A person suffering from severe, untreated schizophrenia develops a complex delusional system where they believe a specific public figure is a demon sent to destroy the world. Acting on these delusions, they attempt to harm the public figure, genuinely believing they are performing a heroic act to save humanity.

  Explanation: In this case, the individual's mental disease (schizophrenia and its associated delusions) prevented them from having the substantial capacity to appreciate the criminality or wrongfulness of their actions. From their perspective, they were not committing a crime but rather fulfilling a necessary, righteous duty.

• Example 2 (Conform Conduct): An individual with a severe impulse control disorder, exacerbated by a diagnosed neurological condition, experiences an overwhelming, uncontrollable urge to shoplift an item, despite knowing it is illegal and having no financial need for it. They understand that shoplifting is wrong and against the law, but their mental and neurological condition makes them unable to resist the impulse.

  Explanation: Here, the person's mental and neurological condition impairs their substantial capacity to conform their conduct to the requirements of the law. Even though they intellectually understand the wrongfulness of shoplifting, their ability to control their actions is significantly compromised.

• Example 3 (Complex Impairment): A veteran suffering from severe Post-Traumatic Stress Disorder (PTSD) experiences a sudden, intense flashback to a combat zone during a non-threatening situation. In this dissociative state, they perceive a bystander as an enemy combatant and react with extreme force, believing they are fighting for their life.

  Explanation: This scenario illustrates how a mental disease (severe PTSD leading to a dissociative flashback) could impair both aspects of the ALI test. The individual, during the flashback, lacked the substantial capacity to appreciate the criminality of their actions because they genuinely believed they were in a life-or-death combat situation. Simultaneously, they lacked the substantial capacity to conform their conduct to the requirements of the law because their actions were an involuntary, primal response driven by their mental state, not a conscious choice.