A Durham rule, product test, or product defect rule is a rule in a

criminal case Criminal law is the body of law that relates to crime. It prescribes conduct perceived as threatening, harmful, or otherwise endangering to the property, health, safety, and moral welfare of people inclusive of one's self. Most criminal law i ...

by which a

jury A jury is a sworn body of people (jurors) convened to hear evidence and render an impartiality, impartial verdict (a Question of fact, finding of fact on a question) officially submitted to them by a court, or to set a sentence (law), penalty o ...

may determine a defendant is not guilty by reason of insanity because a

criminal act In ordinary language, a crime is an unlawful act punishable by a state or other authority. The term ''crime'' does not, in modern criminal law, have any simple and universally accepted definition,Farmer, Lindsay: "Crime, definitions of", in Can ...

was the product of a mental disease. Examples in which such rules were articulated in

common law In law, common law (also known as judicial precedent, judge-made law, or case law) is the body of law created by judges and similar quasi-judicial tribunals by virtue of being stated in written opinions."The common law is not a brooding omnipresen ...

include '' State v. Pike'' (1869) and '' Durham v. United States'' (1954).''Criminal Law - Cases and Materials'', 7th ed. 2012,

Wolters Kluwer Law & Business Wolters Kluwer N.V. () is a Dutch information services company. The company is headquartered in Alphen aan den Rijn, Netherlands (Global) and Philadelphia, United States (corporate). Wolters Kluwer in its current form was founded in 1987 with a m ...

; John Kaplan,

Robert Weisberg Robert I. Weisberg is an American lawyer. He is an Edwin E. Huddleson, Jr. Professor of Law at Stanford Law School, and an expert on criminal law and criminal procedure, as well as a leading scholar in the law and literature movement. Weisberg wa ...

, Guyora Binder,

/ref> In ''Pike'', the court wrote, "An accused is not criminally responsible if his unlawful act was the product of mental disease or mental defect." The ''Durham'' rule was abandoned in the case '' United States v. Brawner'', 471 F.2d 969 (1972). After the 1970s, U.S. jurisdictions have tended to not recognize this argument as it places emphasis on "mental disease or defect" and thus on testimony by

psychiatrists A psychiatrist is a physician who specializes in psychiatry, the branch of medicine devoted to the diagnosis, prevention, study, and treatment of mental disorders. Psychiatrists are physicians and evaluate patients to determine whether their sy ...

and is argued to be somewhat ambiguous. The problem with the "product test" was that it gave psychiatric and psychological experts too much influence in a decision of insanity and not enough to jurors. Although an expert witness may testify as to his opinion in a trial, judges are reluctant to allow it when the opinion goes to the ultimate issue of a case, i.e. when the opinion alone could decide the outcome of a case. The product test asked

expert witness An expert witness, particularly in common law countries such as the United Kingdom, Australia, and the United States, is a person whose opinion by virtue of education, training, certification, skills or experience, is accepted by the judge as ...

es to use their judgment in determining whether criminal actions were "'the product' of a mental disease or defect." It is the jury's job to decide whether a defendant's actions were the product of his mental disease or defect. The expert witness' job is to determine whether the defendant possesses a mental disease or defect. Further, often conflicting 'expert witnesses' were put on the witness stand by the prosecution and defense to draw the opposite conclusions regarding the cause of an individual's actions.

References

See also