more than two years, and then only by legisla tive action, that a new trial was obtained. Then was it discovered that there was nothing in the prosecution's case. The expert on which it relied, though respectable and conscientious, had been guided by tests which recent science had shown to be worthless. The court ordered the acquittal on the ground that there was not even a prima facie case of the corpus delicti. But a cruel wrong had been done to the accused by the first trial, as well as a great scandal to public justice.

Where the question is whether there is unsoundness of mind of a person sufficient to avoid a contract or will made by him, it has been held improper to inquire of a medical expert whether he had sufficient mental capacity to transact business or to make a will, as that is a matter of law : Fairchild v. Bascom, 35 Vt. 398. The proper mode of procceding in such a case would seem to be to take the facts proved by the expert witness or others relating to the subject, or admitted, and assuming them to be true, inquire of the witness if in his judgment they were indicative of inanity or unsoundness of nind: See Woodbury

v. Obear, 7 Gray (Mass.), 476; People v. McCann, 3 Park. C. R. (N. Y.) 272; R. v. Higginson, 1 Car. & K. (Eng.) 129; R. v. Francis, 4 Cox C. C. (Eng.) 57; R. v. Richards, 1 F. & F. (Eng.) 87.

§ 5. Opinions of medical experts as to sanity on hypothetical cases.

It is admissible for an expert or professional witness to give an opinion of a party's sanity, on a hypothetical case, whether it be for the purpose of determining the competency of the party to contract or to make a will, or his liability for crime. And he may be interrogated as to his opinion of certain designated facts presented in a case, supposing them to be true: United States v. McGlue, 1 Curtis (U. S. C. C.), 1; Fairchild v. Bascomb, 35 Vt. 398; Negro Jerry v. Townshend, 9 Md. 145; State v. Windsor, 5 Har. (Del.) 512; Davis v. State, 35 Ind. 496; State v. Kilingler, 46 Mo. 224; McAlister v. State, 17 Ala. 434; Wetherbee v. Wetherbee, 38 Vt. 454

But counsel are limited in propounding questions to the case as presented by the evidence: State v. Stokeley, 16 Minn. 282. Hence, while medical experts may give their opinions in cases where the facts are not disputed, such expert s

are confined, where there is a conflict of testimony, to answers to a hypothetical case: 1 Whart. C. L. (7th ed.), § 50 d; Wilkinson v. Mosely, 30 Ala. 562; Commonwealth v. Rogers, 7 Met. (Mass.) 500.

In the case last cited will be found, in the able opinion of Chief Justice Shaw, a clear and succinct statement and exposition of the law on this subject, as follows: "The opinions of professional men on a question of this description are competent evidence, and in many cases are entitled to great weight and respect. The rule of law on which this proof of the opinion of of witnesses who knew nothing of the actual facts of the case is founded, is not peculiar to medical testimony, but is, as a general rule, applicable to all cases where the question is one depending on skill and science in any particular department. In general it is the opinion of the jury which is to govern, and this is to be formed upon the proof of facts laid before them. But some questions lie beyond the scope of the observation and experience of men in general, but are quite within the observation and experience of those whose peculiar pursuits and profession

have brought that class of facts frequently and habitually under their consideration. Shipmasters and seamen have peculiar means of acquiring knowledge and experience in whatever relates to seamanship and nautical skill. When, therefore, a question arises in a court of justice upon the subject, and certain facts are proved by other witnesses, a shipmaster may be asked his opinion as to the character of such facts. The same is true in regard to any question of science, because persons conversant with such science have peculiar means, from a larger and more exact observation, and long experience in such department of science, of drawing correct inferences from certain facts, either observed by themselves or testified to by other witnesses. familiar instance of the application of this principle occurs very often in cases of homicide, when, upon certain facts being testified to by other witnesses, medical persons are asked whether, in their opinion, a particular wound pescribed would be an adequate cause, or whether such a wound was, in their opinion, the actual cause of death in the particular case. Such question is commonly asked without objection;

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and the judicial proof of the fact of killing often depends wholly or mainly upon such testing of opinion. It is upon this ground that the opinion of witnesses who have long been conversant with insanity in its various forms, and who have had the care and superintendence of insane persons, are received as competent evidence, even though they have not had opportunity to examine the particular patient, and observe the symptoms and indications of disease at the time of its supposed existence. It is designed to aid the judgment of the jury in regard to the influence and effect of certain facts which lie out of the observation and experience of persons in general. And such opinions, when they come from persons of great experience, and in whose correctness and sobriety of judgment just confidence can be had, are of great weight, and deserve the respectful consideration of a jury. But the opinion of a medical man of small experience, or one who has crude and visionary notions, or who has some favorite theory to support, is entitled to very little consideration. The value of such testimony will depend mainly upon the experience, fidelity, and impartiality of the witness who gives