In a criminal trial, temporary insanity is a defense that can be raised to assert that, at the time of the commission of the offense, the defendant, as a result of severe mental disease or defect, was unable to appreciate the nature or wrongfulness of the defendant's acts. This defense is commonly used to contest the specific intent or mens rea required for certain offenses.
In some jurisdictions, courts do not differentiate between the temporary insanity defense and the traditional insanity defense, recognizing that insanity at the time of the offense is sufficient to raise a defense. For example, Colorado has asserted that "a defendant who was found to be legally insane at the time of the offense, but shortly thereafter regains sanity, may assert insanity as an affirmative defense."
While jurisdictions differ in the requirements to demonstrate temporary insanity, the Supreme Court of Iowa has offered a representative standard, stating that:
“In order to be an excuse and defense for a criminal act, the person accused, and who claims [temporary] insanity as a defense, must prove that the crime charged was caused by mental disease or unsoundness which dethroned, overcame, or swayed her reason and judgment with respect to that act, which destroyed her power rationally to comprehend the nature and consequences of that act.”
Temporary insanity is often tied to intoxication, and courts have recognized intoxication as valid grounds to assert the defense. For example, Texas courts have held that while voluntary intoxication cannot excuse a crime, if the use of alcohol produces a state of mind that renders a defendant incapable of knowing the act that he is doing is wrong and criminal, then temporary insanity can be asserted to reduce the resulting penalty. Similarly, California has held that voluntary intoxication may establish temporary insanity as a partial defense to a criminal charge.
Lastly, jurisdictions like Florida, Arkansas, and Kentucky reject assertions of temporary insanity on the basis of extreme emotion, anger, and passion. Nonetheless, offenses committed under extreme emotional distress may still qualify for defenses such as crime of passion and extreme emotional distress.
[Last updated in September of 2021 by the Wex Definitions Team]