MEDICAL EVIDENCE. Testimony given by physicians or surgeons in their pro fessional capacity as experts, or derived from the statements of writers of medical or sur gical works.
This kind of evidence was first recognized by Charles V. of Germany, and incorporated in the "Caroline Code," framed at Ratisbon in 1532, wherein it was ordained that the opinion of medi cal men—at first surgeons only—should be received in oases of deati2 by violent or unnatural means, when suspicion existed of a oriminal agency. Tbe publication of this eode encouraged the members of the medical profession to renewed activity, tend. ing greatly to advance their sciences and the cause of justice generally. Many books soon appeared on the subject of medical jurisprudence, and the importance of medical evidence was more fully understood. Elwell, Malp. & Med. Ev. 285.
2. The evidence of the medical witness iS strictly that of an expert. Elwell, Malp. & Med. Ev. 275 ; 10 Hovv. Pract. N. Y. 289 ; 2 Conn. 514; 1 Chandl. Wisc. 178 •, 2 Ohio; 452 ; 27 N. H. 157 ; 17 Wend. N. Y. 136 ; 4 Den. N. Y. 311 ; 7 Cush. Mass. 219 ; 1 Phil lipps, Ev. 780 ; Smith, Lead. Cases.
The professional witness should not be permitted to make up an opinion to be given in evidence from what other witnesses say of the facts in the case; because under such cir cumstances he takes the place of the jury ae to the credibility of the witness, and in that case he also determines what part of the tes timony of other witnesses properly applies to the case,—a duty thatbelongs to the court. In the case of Rogers, 7 Mete. Mass. 505, C. J. Shaw presiding, the court held : " If the symptoms and indications testified to by other witnesses are proved, and if the jury are sa tisfied of the truth of them, whether in his [the witness's] opinion the party was insane, and what the nature and character of that insanity; and what state did they indicate, and what he would expect would be the con duct of such a person in any supposed cir cumstance." Under this ruling the medical witness passes upon the condition of the per son whose condition is at issue. To do it correctly, he must hear all the evidence that the jury hears ; he must judge as to the rele vance of the evidence of others, and make an application of the facts that legally and pro perly bear upon the case to it, and reject all others: in short, he is judge and jury in the case. Since the trial of Rogers, a different rule has been adopted by the courts in Massa chusetts. the case of the United States vs. McGlue, reported in 1 Curt. C. C., Mr. Jus tice Curtis instructed the jury that medical experts " were not allowed to give opinions in the case. It is not the province of the ex pert to draw inferences of fact from the evi dence, but simply to diecloee his opinion on a known or hypothetical state of facte ; anti, therefore, the counsel on each side have put to the physicians such states of fact as they deem warranted by the evidence, and have taken their opinions thereon. If you con eider any of these states of fact put to the medical witness are proved, then the opinions thereon are admissible to be weighed by you; otherwise their opinions are not applicable to the case." In the McNaughten Case, 10 Clark & F. Han. L. 210, the twelve judges. held in the same way. The attention of the witness being called to a definite state of facts constituting a hypothetical case, his opinion is then unembarrassed by any colla teral questions or considerations, and the jury, under the instructions of the court, de termines haw far the facts sustain the hypo thetical case, and, consequently, how far the opinion of' the witness applies to the case un der investigation. See Elwell, Malp. & Med.
Ev. 311.
3. The medical witness is not a privileged witne§s. A difference of opinion has existed among medico-legal writers, and perhaps still exists. Fonblaanque, a distinguished English barrister, holds that when the ends of justice absolutely require the disclosure, a medical witness is not only bound but compellable to give evidence on all matters that will en lighten the case ; and in the important case of the Duchess of Kingston, Lord Mansfield said, " In a court of justice medical men are bound to divulge secrets when required to do so. If a medical man was voluntarily to re veal these secrets, to be sure he would be guilty of a breach of honor and of great in discretion ; but to give that information, which, by the law of the land, he is bound to do, will never be imputed to him as any in discretion whatever." In this case Sir C. Hawkins, who had attended the duchess as medical man, was compelled to disclose what had been committed to him in confidence. While this is the common-law rule, the states of New York, Missouri, Wisconsin, Iowa, Indiana, Michigan, and perhaps some others, have enacted statutory provisions relieving the physician from the obligation of the common-law rule to reveal professional secrets. The language used in the statutes generally is, " No person duly authorized to practise physic or surgery shall be allowed to disclose any information which he may have acquired in attending a patient in a professional cha racter, and which information was necessary to enable him to prescribe for such patient as a physician, or to do any act for him as a surgeon." Under this statute, in New York it has been held that when a physician was consulted by the defendant in an action on the case for seduction, as to the means of pro ducing abortion, he cannot claim the protec tion of the statute, not being privileged. 21 Wend. N. Y. 79 ; Elwell, Malp. & Med. Ev. 320.
4. Medical books are not received in evi dence. They are subject to the same rule that applies to scientific and other profes sional books. Even the elementary works on law are not admissible in evidence as to what the law' is. 5 Carr. & P. 73; 2 Carr. & K. 270. In the case of Commonwealth vs. Wil son, 1 Gray, 338, Shaw, J. C., said, "Facts or opinions on the subject of insanity, as on any other subject, cannot be laid before the jury except by the testimony under oath of persons skilled in such matter. Whether stated in the language of the court or of the counsel in a former elle, or cited from works of legal or medical writers, they are still statements of facts, and must be proved on oath. The opinion of a lawyer on such a question of fact is entitled to no more weight than that of any other person not an expert. The principles governing the admissibility of such evidence have been fully considered by this court since the trial of Rogers ; and the more recent English authorities are against the admission of such evidence." 6 Carr. & P. 586; Elwell, Malp. & Med. Ev. 332.