The Law and Medical Men

by R. Vashon Rogers

Any one offered as an expert who cannot establish the fact of special knowledge or skill, in the particular department which he is called upon to illuminate, will be rejected. A Court before permitting an expert to testify may examine him, or hear evidence, to satisfy itself that the witness is really what he assumes to be ([286]). |114|

“We find no test laid down,” says the Supreme Court of Indiana, “by which we can determine with mathematical precision just how much experience a witness must have had, how expert, in short, he must be, to render him competent to testify as an expert.” But it is for the Court to decide, within the limits of a fair discretion, whether the experience of the proposed expert has been such as to make his opinions of any value; mere opportunities for special observation will not be deemed sufficient ([287]).

While the Court, or Judge, determines the competency of the witness to testify as an expert, the weight to be accorded to his testimony is for the jury to decide. The testimony of an expert is to be weighed and tested like any other kind of evidence, and is to receive just such credit as the jury may think it entitled to. It is intended to enlighten their minds, not control their judgment ([288]). The jury are not bound by the opinions of medical experts: they may weigh their opinions like any other evidence. They may act against the greater number of opinions and in favour of the fewer; for the opinion of one expert may, on account of his greater knowledge and experience on the subject, or from his giving further details of the case, or more probable reasons for his opinions, be of greater value to the jury than the opposite opinions of several ([289]).

Ordronaux holds that a physician, although confessedly possessing the ordinary experience of his profession, may quoad some particular problem in medical science not be an expert in the best and most critical sense of the term. Non omnes omnia possumus. Once received as an expert, |115| the maxim “Cuilibet in sua arte perito credendum est,” must be applied, and he cannot be contradicted by any unskilled person ([290]).

In 1869, the Chief Justice of the Kentucky Court of Appeal well said, that “the opinions of experts not founded on science, but on a mere theory of morals or ethics, whether given by professional or unprofessional men, are wholly inadmissible as evidence.” Hence the opinion of even physicians that no sane man in a Christian country would commit suicide, not being founded on the science or phenomena of the mind, but rather a theory of morals, religion and future responsibility, is not evidence ([291]).

In the matter of expert testimony, as in other matters, the law does not recognize any particular school of medicine to the exclusion of others. The popular axiom that doctors differ is as true now as ever it was, and so long as it continues to be so, it is impossible for the law to recognize any class of practitioners, or the followers of any particular system, or method of treatment, as exclusively entitled to be regarded as “doctors” ([292]).

The physician called to give evidence as an expert should understand at the outset that he is not called to express any opinion upon the merits of the case, but only on some questions of science raised by the facts proved; that he has no concern in the issue of the trial, and that whichever side calls him he is in no wise the witness—much less the advocate—of that side. He is truly an adviser of the Court, an amicus curiæ, rather than a party interested in the result of the trial. Balbus in his commentaries on the code says, “Medici proprie non sunt testes, sed est magis judicium quam testimonium.” Experts, no matter on what |116| they testify, simply supply data, as to whose competency, relevancy and weight, the Court is to judge, and as to which the Court is finally to declare the law. Where the facts testified to by experts are undisputed, and when they are the results of a particular science or art, with which such experts are familiar, then the Court accepts such facts, and declares the law that therefrom springs; where the facts are disputed then the jury is to determine where the preponderance of proof lies. But when the testimony of the expert touches either law or speculation, psychology or ethics, then such testimony is to be received as mere argument, which if admissible at all is to be treated simply as if addressed to the judgment of the Court ([293]).

In his examination in chief an expert may not only give his opinion itself, but also the grounds and reasons of it; in fact it has been held that it is his duty to state the reasons of his opinion and the facts on which it is based, and if it is not sustained by them it is entitled to little weight ([294]).

The opinion of a medical man is admissible upon, the condition of the human system at any given time; the nature and symptoms of disease; the nature and effects of wounds; the cause of death; the cause or effect of an injury; the character of the instrument with which a wound was produced; the effect of a particular course of treatment; the likelihood of recovery; the mental condition of a person; and on similar subjects. For instance, where one was indicted for endeavouring to procure abortion, the opinion that the woman was pregnant at the time is relevant ([295]). Where the question was whether a certain |117| blow was sufficient to cause death; or whether a wound and fracture on the head was caused by a fall; or whether the fractures of the skull were caused by a gun; or whether a gun-shot wound caused death; the opinions of physicians were held admissible ([296]). The opinion of medical experts will be received upon the question as to whether an abortion has been performed, or whether certain drugs are abortives, or certain instruments adapted to produce an abortion ([297]). Experts may testify, after having made a chemical analysis of the contents of the stomach, as to the presence of poison in the body; and, without such analysis of a mixture, a chemist may speak of its ingredients ([298]). Those accustomed to make chemical and microscopic examinations of blood and blood stains may speak as to whether certain stains are made by human or other blood. So, too, they may speak as to the ink in questions as to handwriting ([299]). So, too, they may be asked their opinions touching the permanency of any injury forming the subject of an action. Also, in an action for damages against a railway company, a physician may be asked at what period after the injury the plaintiff would be most likely to improve, if he were going to recover at all ([300]). Where Barber sued Meriam for injury to his wife, and she had been treated professionally for some weeks by Dr. H., the opinion of another physician as to the effect of Dr. H.’s treatment was considered |118| admissible ([301]). And so in a case of malpractice a medical man may be asked whether the practice pursued was good practice ([302]). He may be asked as to the nature and properties of the medicines employed by another physician in the case in question; also, as to the practice with regard to consultations; also, whether, in his opinion, a patient’s death was or was not the result of neglect or want of skill on the part of the attending physician ([303]). But he cannot be asked his opinion as to the general skill of the physician on trial; nor the general reputation of the school which the doctor in trouble attended; nor can he say whether, from all the evidence in the case, the defendant was guilty of malpractice, for that is the question for the jury; nor can he say whether a physician has honorably and faithfully discharged his duty to his professional brethren ([304]).

It has been held that a medical witness may give his opinion upon new and hitherto unknown cases whenever he swears that he can form such an opinion, even though at the same time he should admit that precisely such a case had never before fallen under his observation, nor under his notice in the books. The man of science is distinguished from the empiric in nothing more than in not relying on specifics, and also not waiting for the exact similitudes in things material and immaterial before forming a judgment as to their similarity ([305]).