The determination of one’s criminal responsibility or blameworthiness is a complex and controversial issue. When a crime or “actus reus” (Latin: bad act) has been committed, the assessment of one’s level of criminal responsibility depends largely on the person’s mental state and intention at the time when the criminal act was done. The decision on one’s guilt depends on whether there is evidence that the person accused of the criminal violation had acted with “mens rea” (Latin: guilty mind).
One of the best known approaches to define what insanity means is called the “M’Naghten Test.” The “M’Naghten Test” was drafted by the House of the Lords in Great Britain subsequent to a public outcry after the insanity acquittal of Daniel M’Naghten. Mr. Daniel M’Naghten set out to assassinate the British Prime Minister Robert Peel, but he killed Mr. Peel’s private secretary instead. The M’Naghten test stated: “To establish a defense on the ground of insanity, it must be clearly proved that, at the time of the committing of the act, the party accused was laboring under such a defect of reason, from disease of the mind, as not to know the nature and quality of the act he was doing; or, if he did know it, that he did not know he was doing what was wrong.”
Later, in a D.C. District Court of Appeals case (US v. Brawner, 1972), the Court decided to make the determination of whether the accused is criminally responsible or not based on a Model Penal Code drafted by the American Law Institute (ALI) which tested for insanity by: “A person is not responsible for criminal conduct if at the time of such conduct as a result of mental disease or defect he lacks substantial capacity either to appreciate the criminality [wrongfulness] of his conduct or to conform his conduct to the requirements of the law.” (American Law Institute, 1985, Sec. 4.01)
When there might be reasons to suspect that an accused might have committed a crime without “mens reas” (evil or guilty intent), a defense attorney (or the court) might raise the question of one’s criminal responsibility. Once the accused’s sanity is in question, a “Criminal Responsibility” evaluation is needed. The assessment of one’s criminal responsibility is usually conducted by a forensic psychiatrist or a forensic clinical psychologist.
According to the “Insanity Defense Reform Law,” passed in 1984 after a jury acquitted John Hinckley Jr. of the attempted assassination of Ronald Reagan, the burden of proof that the accused is insane lays on the defense. To qualify for an insanity defense, the defense has to prove to a standard of “Clear and Convincing” (i.e. more than 75% certainty) that the defendant is indeed mentally ill to the point that he “lacks the ability to appreciate the criminality of his conduct.”
For insanity defense, the volitional prong of argument and diminished capacity defense are also dropped. Court-appointed psychologists and psychiatrists might conduct interviews (with the defendant and other pertinent individuals), collect and review collateral evidence (such as letters, medical records, and other documents), and administer forensic assessment and forensic relevant tests to provide their professional opinions on the accused’s criminal responsibility.
About the author:
Dr. Grace Graham is a licensed clinical psychologist and therapist with over 20 years’ experience. She has testified as a forensic witness in several cases.