The decision about whether or not to retain the insanity defense is a moral issue that focuses on the justness of attributing criminal responsibility to and punishing a person whose behavior is a product of severe mental illness at the time of the offense at issue. The insanity defense must be retained because a just criminal justice system must base guilt and innocence and degrees of guilt on the characteristics of the defendant's mental state and culpability underlying the behavior at issue. Many accept this principle but are dissatisfied with its application in the current insanity defense. Proposed alternatives focus on the actus reus and mens rea doctrines as elements of an offense, sentencing discretion, and the guilty-but-mentally-ill verdict. None of these alternatives complies with the principle that severely mentally ill persons are not criminally responsible for their behavior. A defendant should be not guilty by reason of insanity if at the time of the offense he/she was 'extremely crazy and the craziness affected the criminal behavior.' Persons acquitted by reason of insanity should be civilly committed only for as long as required to heal the sickness underlying the dangerous behavior, without reference to any penalty for the charged crime. Mental health experts should not be involved in deciding whether or not a person is insane by legal definition. Experts should be limited to clinical descriptions of defendants' thoughts, feelings, and actions.