Chalmers, C. J.,
delivered the opinion of the court.
The opinions of non-experts as to the sanitj7 or insanity of persons with whom they are acquainted is receivable in evidence. Their opinions are not receivable in answer to hypothetical questions, or upon statements of facts deposed to by other witnesses. This is the province of experts only. Whether a man is sane or not, is always more or less a matter of opinion; and while insanity, in some cases, is so well developed as to admit of no doubt, it can never be regarded as standing upon the same footing as the happening of a physical fact, like birth, or death, or presence, at or absence from a particular place.
How much weight is to be given to the opinion of a witness on the question of insanity depends, like the weight to be given to all other opinions, upon the intelligence of the witness and his opportunities of observation; and while the testimony of a professional man, with equal opportunities, would ordinarily be more reliable than that of a non-professional, the testimony of -an intelligent friend who had known the subject of the inquiry for years, might be more weighty than that of the most experienced expert who had seen him *743only since the condition of his intellect had become a matter of investigation. Craft and deceit might mislead the one into-an error which the lifetime acquaintance and observation of the other would readily detect. The authorities on the subject are by no means uniform. Some deny the right of the non-expert to give an opinion at all; some admit the opinion, provided it be accompanied by a statement of the facts upon which it is based, while others admit it without restriction. We agree with Mr. Wharton in thinking that the qualification that the opinion of the non-expert must be accompanied by a statement of the facts upon which it is based, is not very important, since, whether the witness be an expert or non-expert, the grounds of his belief and his opportunities of observation may always be elicited ; and whether the witness b of the one class or the other, his testimony should be rejected by the court where it consists of a mere nakqd declaration of opinion, with neither learning, observation, nor acquaintance to support it. The sounder rule, we think, is to admit the opinions of non-experts, accompanied by a statement of the facts on which they are based, whenever the witness has had such acquaintance or opportunities of observation as- are likely to make his opinion valuable. The correctness of such a rule is even more apparent in cases of alleged idiocy and mental imbecility than in cases of insanity or violent forms of madness. 2 Whart. on Ev. 451, 452, sect. 451, and cases cited ; Clary v. Clary, 2 Ired. L. 78.
Judgment reversed.