counsel answered in the negative saying that the only objection was that it was “within the province of this jury to determine what happened without having some thirteenth juror to come in and testify to what happened. ’ ’
The general rule is “that witnesses must testify to facts, and not to opinions, and that whenever the question to be determined is the result of the common experience of all men of ordinary education, or is to be inferred from particular facts, the inference is to be drawn by the jury, and not by the witness,” (Sappenfield v. Main St. etc. R. R. Co., 91 Cal. 48, 59 [27 P. 590]).
The question presented for decision is whether the proffered testimony was within that rule or whether it was within the purview of section 1870, subdivision 9, Code of Civil Procedure which provides that the opinion of a witness is admissible “on a question of science, art, or trade, when he is skilled therein,” because it deals with “matters not presumably within the common knowledge of men” (Callan v. Bull, 113 Cal. 593, 607 [45 P. 1017]), and “was proper and necessary to an enlightened consideration and a correct disposition of the ultimate issue” (Fonts v. Southern Pacific Co., 30 Cal.App. 633, 641 [159 P. 215]).
In the first place, it must be borne in mind that it has to be assumed for the purposes of this appeal that had the witness been permitted to testify, his testimony would have been as indicated by the tender
(O’Conor v. Braly, 112 Cal. 31, 37 [44 P. 305, 53 Am.St.Rep. 155]; 5 C.J.S. 331).
“Expert testimony has been uniformly sanctioned as proper, if not, indeed, well-nigh indispensable in many instances, particularly in jury trials, to the crystallization of intelligent and just results. Under the common law the admissibility of the opinion of experts upon matters within the field of their knowledge was well established. ...” (10 Cal.Jur. 957.)
It might be added that section 1870, subdivision 9 is but a legislative enactment of the common law rule. (Estate of Toomes, 54 Cal. 509, 513 [35 Am.Rep. 83].)
The testimony of an expert is admissible “because a man’s professional pursuit, his peculiar skill and knowledge in some department of science, not common to men in general, enable him to draw an inference, where men of common experience, after all the facts proved, would be left in doubt.” (10 Cal.Jur. 958.)