Legal Definitions - ALI test

The ALI test, which stands for the American Law Institute test, is a legal standard used in some jurisdictions to determine if a criminal defendant should be found "not guilty by reason of insanity." It is also commonly referred to as the Substantial-Capacity Test.

This test asks whether, at the time of the crime, the defendant suffered from a mental disease or defect that prevented them from having the "substantial capacity" to either:

• Understand and appreciate that their conduct was wrong (its criminality); OR
• Control their behavior and conform it to what the law requires.

Unlike older, stricter insanity tests, the ALI test provides a more flexible approach, acknowledging that mental illness can impair a person's ability to understand wrongfulness *or* control their actions, without requiring total incapacitation. It focuses on whether the person lacked a significant, rather than complete, ability in these areas.

Here are some examples to illustrate how the ALI test might be applied:

• Example 1: Impaired Appreciation of Wrongfulness

  A person suffering from severe paranoid delusions, believing that their neighbor is a secret agent actively plotting to poison them, breaks into the neighbor's home to disable what they perceive as a "poison gas device" (which is actually a humidifier). During this act, they cause significant property damage. If charged with burglary and vandalism, their defense might argue that due to their profound mental illness, they lacked the substantial capacity to appreciate the criminality (wrongfulness) of their actions. They genuinely believed they were acting in self-preservation against a perceived threat, not committing a crime against an innocent person.

• Example 2: Impaired Capacity to Conform Conduct

  An individual with a diagnosed severe impulse control disorder, characterized by sudden, overwhelming urges to set fires, finds themselves in a stressful situation. Despite knowing that arson is illegal and attempting to resist the urge, they experience an uncontrollable compulsion and light a small fire in a dumpster. In court, their defense could argue that while they understood the wrongfulness of setting fires, their mental defect deprived them of the substantial capacity to conform their conduct to the requirements of the law, meaning they could not control their actions despite knowing they were wrong.

• Example 3: Complex Mental State Affecting Both

  A veteran suffering from severe Post-Traumatic Stress Disorder (PTSD) with dissociative episodes experiences a sudden, intense flashback triggered by a loud, unexpected noise in a crowded public place. During the flashback, they genuinely believe they are back in a combat zone and react violently to a perceived enemy, injuring a bystander. The defense might contend that during the dissociative episode, the individual lacked the substantial capacity to appreciate the criminality of their actions because they were not perceiving reality accurately. Additionally, or alternatively, they could argue that the overwhelming nature of the trauma-induced flashback meant they lacked the substantial capacity to conform their conduct to the law, as their actions were an involuntary, defensive response within their deluded state.