In the case of Stevens v. The State of Indiana, the instruction to the jury, that, if they believed the defendant knew the difference between right and wrong in respect to the act in question, if he was conscious that such act was one which he ought not to do, he was responsible—was held to be erroneous.
It would appear, then, that the American courts, which, having inherited the common law of England, at first followed docilely in the wake of the English courts, are now exhibiting a disposition to emancipate themselves from an authority which they perceive to be founded on defective and erroneous views of insanity, and a desire to bring the law more into accordance with the results of scientific observation. The decisions of the court of New Hampshire in Boardman v. Woodman, State v. Jones, and State v. Pike, are especially worthy of attention for their searching discussion of the relations of insanity to jurisprudence, and for the decisive abandonment of the right-and-wrong test of responsibility. In the case of State v. Pike, Chief-Justice Perley instructed the jury that they should return a verdict of not guilty "if the killing was the offspring of mental disease in the defendant; that neither delusion nor knowledge of right and wrong, nor design or cunning in planning and executing the killing, and in escaping or avoiding detection, nor ability to recognize acquaintance, or to labor or transact business or manage affairs, is, as a matter of law. a test of mental disease; but that all symptoms and all tests of mental disease are purely matters of fact to be determined by the jury."