1 observation; and "whether the means of information or facts proved, or the conclusions drawn by the witness are of the satisfactory character required to base a finding upon, or not, is for the consideration of the jury, under proper instructions." 2 In Massachusetts the rule seems to be that an opinion cannot be given, but any facts noticed by the witness, such as incoherence or change in intelligence, may be testified to, even though the witness is not an expert and did not attest the will.3 In Ohio the opinion of the witness must relate to the time of his examination; and upon the direct exami 1 Hathaway v. Nat. Life Ins. Co., 48 Vt. 335; Doe v. Reagan, 5 Blackf. (Ind.) 217. See Dicken v. Johnson, 7 Ga. 484. "Such opinions were excluded upon the theory, that special knowledge and skill were required to judge intelligently of the mental condition of another, and that if the witnesses gave a detailed account of the acts and conduct of the person whose mental capacity was in question, the jury was as competent to form an opinion thereon, as the witnesses themselves. That the opinions of professional witnesses should be received, as they could judge with some degree of accuracy, from pathological symptoms; but as non-professional witnesses could only form their opinions from the actual demonstrations of the person, those demonstrations should be stated to the jury, and that body left to form their own opinion as to the cause and character of the appearances described. The fact has come, however, to be generally recognized, that it is impossible so to describe the appearance and demonstrations of a person, as to convey any accurate idea of their exact character, and to leave upon the mind of jurors the legitimate impressions which such demonstrations and appearances naturally leave upon the mind of the actual observer. The result has been that many of the earlier cases have been overruled, and the principle has come to be generally recognized that nonprofessional witnesses may give their opinions as to sanity, as a result of their personal observation of the person whose mental condition is in question, after first stating the facts which they observed." Rogers on Exp. Test. § 61, citing many cases. "No In Alabama the court says: precise rule can be laid down as to the length or character of acquaintance which would render the opinion of a person not a physician admissible evidence on a question of insanity. In case of general insanity, a total incapacity to distinguish right from wrong on any question, the same degree of observation is not required to discover the existence of the disease as in cases of monomania or partial derangement, and therefore the same degree of intimacy is not necessary to render the opinion of the witness admissible; but in every case the circumstances must be such as to have afforded the witness the opportunity of forming an accurate judgment as to the existence or non-existence of the disease, considered with reference to the character or degree in which it is alleged to exist." Powell v. State, 25 Ala. 21. As to who are deemed qualified by intimacy with and observation of the deceased, to give an opinion, see Stukey v. Billah, 41 Ala. 700; Townshend v. Townshend, 7 Gill (Md.) 10; Weems v. Weems, 19 Md. 334; Choice v. State, 31 Ga. 424, 467. McClackey v. State, 5 Tex. App. 2 331. 3 Barker v. Comins, 110 Mass. 477. S. P., May v. Bradlee, 127 Id. 414. nation his opinion at an anterior period cannot be called for; opinion as to the capacity of the And in Vermont the fact that the nor can he be asked his testator to make a will.1 witness did not form his opinion at the time he saw and observed the facts testified to by him, does not render his opinion on that account inadmissible.2 In New Jersey it is held that the mere fact of a man's having affixed his signature to a will as a subscribing witness does not entitle his opinion, as to the competency of the testator, to any more weight than that of any one else who may be called upon to testify.3 4 The New York rule is perhaps the best settled and most satisfactory. In that State non-expert witnesses who have testified to facts bearing upon the mental condition of the testator, cannot state what they thought of his condition of mind, or their impressions as to it; but they may characterize as rational or irrational the acts and declarations to which they have testified, and state the impression produced upon their minds by what they beheld or heard, their examination being limited to their conclusions from the specific facts they disclose, and so confined as to exclude any opinion on the general question of soundness or unsoundness of mind." 1 Runyan v. Price, 15 Ohio St. 1. S. P., Farrell v. Brennan, 32 Mo. 328. But see Wogan v. Small, 11 Serg. & R. (Pa.) 141. 2 Hathaway v. Nat. Life Ins. Co., 48 Vt. 335. 3 Turner v. Cheesman, 2 McCart. (N. J.) 243; Garrison v. Garrison, Id. 266; Boylan v. Mecker, Id. 310. Sisson v. Conger, 1 T. & C. (N. Y.) 564, 569; Real v. People, 42 N. Y. 282. Howell v. Taylor, 11 Hun (N. Y.) 214; Hewlett v. Wood, 55 N. Y. 635; O'Brien v. People, 36 Id. 276; Clapp r. Fullerton, 34 Id. 190; Higbee v. Guardian Mut. Life Ins. Co., 53 Id. 603; People v. Lake, 12 Id. 358; Deshon . Merchants' Bank, 8 Bosw. (N. Y.) 461. For further decisions adopting one or the other of the views given in the text, see Johnson v. State, 17 Ala. 618; State v. Brunetto, 13 La. Ann. 45; State v. Coleman, 27 Id. 691; Dickinson v. Barber, 9 Mass. 225; Com. v. Wilson, 1 Gray (Mass.) 337; State v. Pike, 49 N. H. 399; Sears v. Shaffer, 1 Barb. (N. Y.) 408; McDougald v. McLean, 1 Wins. (N. C.) 120; Wilkinson v. Pearson, 23 Pa. St. 117; Dove v. State, 3 Heisk. (Tenn.) 348. CHAPTER XXVI. EXPERT TESTIMONY. § 292. What Questions call for Expert Testimony. § 293. Qualifications of Experts. - Competency. § 294. Examination of Experts. - Hypothetical Questions. § 295. Physicians, Surgeons, and Chemists. § 296. Persons skilled in the Law. § 297. Surveyors and Civil Engineers. § 298. Mechanics, Artisans, and Persons skilled in a Trade or Vocation. § 299. Experts in Handwriting. § 300. Effect and Value of Expert Testimony. § 292. What Questions call for Expert Testimony. The foundation of the rule admitting evidence of opinions including those of experts in certain cases is necessity.1 The jury are to be enlightened in every possible way, and as they are not selected with a view to their qualifications to try the particular issue before them, but simply as men possessing the ordinary qualifications of mankind, when questions arise to be determined by them, involving an acquaintance with facts not coming within the ordinary range of human experience, skilled witnesses are permitted to enlighten them.2 The true rule is that when the subject to be investigated so far partakes of the nature of a science or trade as to require a previous course of study or habit in order to the attainment of a knowledge of it, opinions of experts are admissible. Otherwise, if the relation of facts, and their probable result can be determined without especial skill or study. In such cases the facts themselves must be given, and the jury left to draw conclusions or inferences.3 1 State v. Clark, 12 Ired. (N. C.) L. 152, 153; City of Chicago v. McGiven, 78 Ill. 347. "It is not because a man has a reputation for sagacity, and judgment, and power of reasoning, that his opinion is 2 Moreland v. Mitchell Co., 40 Iowa, admissible; if so, such men might be 394. 8 Muldowney v. Illinois Cent. R. R. Co., 36 Iowa, 462; Rogers Exp. Test. § 5 and cases cited. called in all cases, to advise the jury, and it would change the mode of trial. But it is because a man's professional pursuits, his peculiar skill and knowl It has been said that there are three classes of cases in which the opinions of experts are admissible in evidence: (1) Upon questions of science, skill, or trade, or others of like kind. (2) When the subject-matter of inquiry is such, that inexperienced persons are unlikely to prove capable of forming a correct judgment upon it, without such assistance. (3) When the subject-matter of investigation so far partakes of the nature of a science, as to require a course of previous habit or study, in order to the attainment of a knowledge of it.1 Such opinions are inadmissible where the matter under investigation is of such a nature that it may be presumed to come "within the common experience of all men of common education, moving in ordinary walks of life." 2 edge 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." Per Shaw, C. J., in New England Glass Co. v. Lovell, 7 Cush. (Mass.) 319. 1 Jones . Tucker, 41 N. H. 546. "It is often very difficult to determine in regard to what particular matters and points witnesses may give testimony by way of opinion. It is doubtful whether all the cases can be harmonized, or brought within any general rule or principle. The most comprehensive and accurate rule upon the subject, we believe to be as follows: That the opinion of witnesses possessing peculiar skill is admissible whenever the subject-matter of inquiry is such, that inexperienced persons are not likely to prove capable of forming a correct judgment upon it, without such assistance [followed in Kipner v. Biebl, Alb. L. J. Sept. 3, 1881]; in other words, when it so far partakes of the nature of a science, as to require a course of previous habit or study in order to the attainment of a knowledge of it, and that the opinions of witnesses cannot be received when the inquiry is into a subject-matter, the nature of which is not such as to require any particular habits of study in order to qualify a man to under stand it. If the relation of facts and their probable results can be determined without especial skill or study, the facts themselves must be given in evidence, and the conclusions or inferences must be drawn by the jury." "The true test of the admissibility of such testimony, is not whether the subject-matter is common or uncommon, or whether many persons or few have some knowledge of the matter; but it is whether the witnesses offered as experts have any peculiar knowledge or experience, not common to the world, which renders their opinions, founded on such knowledge or experience, any aid to the court or to the jury in determining the questions at issue." Taylor v. Town of Monroe, 43 Conn. 36, 44. 2 New England Glass Co. v. Lovell, 7 Cush. (Mass.) 319. "If the jury can be put in possession of all the facilities for forming a correct opinion that the witness had, they must come to their conclusions unembarrassed by the opinions of others." Dillard v. State, 58 Miss. 368, 388. "It is only where the matter inquired of lies within the range of the peculiar skill and experience of the witness, and is one of which the ordinary knowledge and experience of mankind *Muldowney v. Illinois Cent. R. R. Co., 36 Iowa, 462. Considerable difficulty has arisen in the application of this rule, plain and simple though it appear when abstractly considered. It has been said that "the principles on which the authorities rest are more consistent than the attempts to apply them." The distinctions between facts lying within, and those lying without the range of common experience and ordinary intelligence, are not always satisfactorily drawn by the authorities.2 does not enable them to see what inferences should be drawn from the facts, that the witness may supply opinions as their guide." Kennedy v. People, 39 N. Y. 245. S. P., Hart r. Hudson River Bridge Co., 84 N. Y. 56, 60, 61. 1 Evans v. People, 12 Mich. 27. 2 The following are a few of the many questions which have been held to be within the range of common experience, and as to which, consequently, expert testimony is not admissible: Whether one building is so near another as to increase the hazard of fire insurance (Milwaukee &c. R. R. Co. v. Kellogg, 94 U. S. 469); whether the wound of which the deceased died could have been inflicted by a pistol-shot fired by the defendant from a certain direction (People v. Westlake, 62 Cal. 303); whether a sidewalk made of rough plank, laid on stringers, is properly constructed or not (Alexander v. Town of Mt. Sterling, 71 Ill. 366); whether plaintiff (a car-coupler) used due care or acted imprudently (Hopkins v. Ind. & St. L. R. R. Co., 78 Ill. 32. S. P., Belair v. C. & N. W. R. Co., 43 Iowa, 667; Muldowney v. Ill. Central R. R. Co., 36 Id. 462); whether glass placed in a sidewalk to afford light to the area below, is unsafe, by reason of the too great smoothness or slipperiness of its surface (City of Chicago v. McGiven, 78 Ill. 347); whether a custom existed that the employment of an architect to make plans and designs for a building, carried with it an employment to superintend its construction (Wilson v. Bauman, 80 Ill. 493); whether a hay wagon loaded in a certain way, was safe for riding over ordinary roads (Bills v. City of Ottumwa, 35 Iowa, 107); whether the falling of the span of a bridge was occasioned by a displacement of the stringers, resulting from the action of snow and ice (Hughes v. Muscatine County, 44 Iowa, 672); whether, in a given case, a shaded object would be rendered visible by a certain artificial light (Weave v. K. & D. M. R'y Co., 45 Iowa, 246); whether an unoccupied building is a more hazardous risk than one occupied (Cannel v. Phoenix Ins. Co., 59 Me. 582); whether a mill-site exists in a particular locality (Clagett v. Easterday, 42 Md. 617); as to the effect of water in disintegrating the mortar of a wall (Underwood v. Waldron, 33 Mich. 232); what hard-pan is, and whether any was found in excavating (Currier v. Boston &c. R. R. Co., 34 N. H. 498); whether a person was intoxicated at a given time (State v. Pike, 49 N. H. 399); whether a railroad train stopped an ample time for all the passengers to get off (Keller v. N. Y. Central R. R. Co., 2 Abb. (N. Y.) App. Dec. 480); whether it be dangerous to use a smoke-stack without a spark-catcher (Teall v. Barton, 40 Barb. (N. Y.) 137); how the running off of cars on the inside of a curve, instead of the outside, can be accounted for (Murphy v. N. Y. Central R. R. Co., 66 Barb. (N. Y.) 125 ); whether a cattle guard is properly constructed (Swartout v. N. Y. Central R. R. Co., 7 Hun (N. Y.) 571. The following have been held to be proper questions for experts: Whether a certain usage existed on a question of navigation not governed by the sailing rules and regulations |