The Durham Rule

Courts have used several legal tests to determine whether someone whose unlawful acts resulting from a mental defect are responsible for their crimes. These tests consider the defendant's mental state during the criminal act.

Suppose a court determines an individual is not guilty by reason of insanity. In general, the judge or jury can't convict them for crimes committed as a result of certain mental conditions. This is known as an insanity defense.

There are four main types of tests used for an insanity plea:

This article discusses the Durham Rule, its origin, and current use.

The Durham Rule: The Basics

According to the Durham Rule, a criminal defendant is not liable for a criminal act if the act resulted from a mental disease or defect the defendant had at the time of the crime. Courts sometimes refer to it as the product test, because the defendant must show their criminal act was the product of a mental disease.

The Durham Rule does not require a diagnosis of a mental illness or disorder. Federal courts and all but one state court have rejected the test for being too broad. For example, drug addicts could use the defense to avoid convictions for crimes related to their addiction.

New Hampshire is the only state still using this rule, but they have narrowed their interpretation to limit the defense to only the most serious cases. New Hampshire also places a fairly strict burden of proof on the defendant when they use the insanity defense. According to the code section, defendants must prove legal insanity by clear and convincing evidence.

Origins of the Durham Rule

New Hampshire courts adopted a version of the Durham Rule in 1871. The rule gained widespread appeal after a 1954 U.S. Court of Appeals for the District of Columbia Circuit decision, the case of Durham v. United States. There, the court found the existing tests for legal insanity inadequate.

Before the Durham Rule, some courts used the M'Naghten Rule, also called the M'Naghten Test. This test centers on the defendant's inability to know right from wrong. Other courts used the Irresistible Impulse Test, which considered the defendant's inability to control impulses. Both the M'Naghten Rule and Irresistible Impulse Test required a clinical diagnosis of insanity.

The Court of Appeals decided that these approaches failed to account for certain defendants who had mental health issues. The Court of Appeals suggested the following test instead:

"The question will be simply whether the accused acted because of a mental disorder, and not whether he displayed particular symptoms which medical science has long recognized do not necessarily, or even typically, accompany even the most serious mental disorder."

Criticism of the Durham Rule

The Durham case established a new approach in federal and some state courts. The Durham Rule quickly came under heavy criticism, as critics argued it lacked a clear legal standard of criminal responsibility. For instance, someone who committed a crime related to a gambling addiction could successfully secure a conviction of not guilty by reason of insanity using the Durham Rule.

Federal and most state courts abandoned the Durham Rule in 1972. All federal circuits and most states now use the Model Penal Code of the American Law Institute to determine whether a defendant qualifies for the insanity defense.

Questions About the Durham Rule? Ask an Attorney

Insanity defenses are common in popular culture, and the defense often works wonderfully in TV and movies. In the real world, however, insanity defenses are much more complicated than this portrayal would lead you to believe. If the government accuses you of a crime for which insanity may be a defense, consider contacting a criminal defense attorney as soon as possible. An experienced attorney can provide legal advice about the following:

  • Specific information about criminal law and criminal acts
  • Your jurisdiction's laws regarding insanity defenses and tests of criminal responsibility
  • Whether the Durham Test applies to your specific case
  • Whether an expert witness or expert testimony is necessary in your case

If you are facing criminal charges, do not delay in contacting a criminal defense attorney.

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