The opinion of the court was delivered by
Eoyce, J.The only exceptions taken on the trial that are now insisted upon are those in reference to the admission of certain questions put to, and the answers to the same given by, the medical experts, Drs. Merkel and Jackson. Those questions called for an opinion from said experts, based in whole or in part upon information derived from reading the deposition given by the plaintiff to be used in the case, and which was used upon the trial. The deposition being admissible as evidence, it could be used for all of and the same purposes that the evidence of the party reciting and detailing the same facts upon the stand could be used for; and hence, if it would have been allowable to call for an opinion from experts who had heard such evidence in court and based upon such evidence, it would be equally allowable to call for an opinion based upon the same evidence taken in the form of a deposition.
It is well settled, both in England and in this country, that hypothetical questions may be put to an expert. The questions assume the' existence of certain facts, and the opinion of the expert is based upon that assumption. The value of an opinion thus given is wholly dependent upon the existence of the facts assumed by the question. The reason for making the opinions of this class of witnesses evidence, and making them exceptions to the general rule which excludes opinions as evidence, was, the necessity for the aid of science and skill in determining questions to the decision of which such aid was absolutely Requisite. It is not for the expert to express any opinion upon the truth or falsity of the facts which are assumed by the question propounded to him, or, if his opinion is based upon evidence, to pass upon the weight to be given to the evidence.
In Fairchild v. Bascomb, 35 Vt. 398, the question was as to the sanity of the testatrix at the time of the execution of her will. The evidence bearing upon the question of her sanity was conflicting. Dr. Eockwell, who was called as an expert, and *726heard all the evidence, was inquired of, if the facts testified to by all the witnesses were true, what, in his opinion, was the mental condition of the testatrix in respect to sanity or insanity at the time of the execution of the will. It was held that permitting the witness to answer that question was error, because it was really asking him for his opinion as to the preponderance of the evidence.
It is claimed that the questions objected to were such that the experts would have to determine what facts the plaintiff’s deposition established, or warranted them in considering as established, before they could give any opinion from the knowledge they derived from it. The same objection might have been made if the whole subject-matter contained in the deposition had been resolved into hypothetical questions; and in such case, as we have seen, the expert gives his opinion upon the assumption that the facts assumed by the question are true. And the further objection, that they may not have found the same facts from the deposition that the jury did, is unfounded, for the reason that the experts had nothing to do in the matter of finding the facts. Their opinions were based upon the assumption that the facts were as the deposition tended to show them. It was the exclusive province of the jury to find the facts; and if they found them materially different from what the deposition tended to show them to be, the foundation upon which the experts based their opinions failed, and the superstructure failed with it.
There can be no doubt but that it would have been allowable to put hypothetical questions to the experts, incorporating into them the subject-matter contained in the plaintiff’s deposition; but it is claimed that it was error to make the deposition the basis upon which the questions were put and answered. This question seems to have been practically settled in Fairchild v. Bascomb. Dr.‘ Rockwell, who was improved as an expert on that trial, was present in court during the examination of the witnesses, and the opinions he gave were based almost wholly upon the testimony that he heard in court; and Judge Aldis, in the opinion, says there is no question but that in this case the opinion of an expert was admissible upon the question of insanity, *727and that such a witness might testify as to the facts proved by other witnesses tending to show insanity, whether they, if true, did or did not indicate partial or total insanity.
Where an expert hears or reads the evidence, there is no reason why he may not form as correct a judgment based upon such evidence, assuming it to be true, as if the same evidence was submitted to him in the form of hypothetical questions; and it would seem to be an idle and useless ceremony to require evidence with which he is already familiar to be repeated to him in that form.
In Hunt v. Lowell Gas Light Co., 8 Allen, 169, three physicians who heard the testimony on the part of the plaintiffs, which was not conflicting, were each asked this question: “Having heard the evidence, and assuming the statements made by the plaintiffs to be true, what, in your opinion, was their sickness; and do you see any adequate cause for the same ? ” Exception was taken to allowing the questions to be put. The Supreme Court held that it was not error; and Chapman, J., in that opinion, says: “The object of all questions to experts should be, to obtain their opinion as to matters of skill or science which are in controversy, and at the same time to exclude their opinion as to the effect of the evidence in establishing controverted facts; ” and that the questions allowed to be put did not require anything more of the witnesses than a scientific opinion. We think the evidence was admissible.
Judgment affirmed.