vided into three general classes: Subscribing witnesses to the will, experts, and lay witnesses generally. This classification is of importance when a witness is called upon to express an opinion. It is the general rule that a witness may testify only as to facts within his personal knowledge, and may not express his opinion or judgment as to matters which the court or the jury is required to determine, or which constitute elements of such determination. There are, however, exceptions to this rule, and where, in a will contest, the question of testamentary capacity is involved, witnesses may, in varying degrees and under varying circumstances, state their opinions.18

§ 375. Subscribing Witnesses Should Satisfy Themselves That the Testator Is of Sound Mind.

The decisions are not harmonious as to whether or not the fact that a witness attests the will of another in effect makes him vouch for the mental capacity of the testator. It may be well, however, to first refer to some of the matters involved. In the absence of statutory requirement, it is not necessary to state in the attestation clause that the testator was of sound mind.49 The witness need

47 Wyman v. Gould, 47 Me. 159; Robinson v. Adams, 62 Me. 369, 410, 16 Am. Rep. 473; De Witt v. Barley, 9 N. Y. 371; s. c., De Witt v. Barley, 17 N. Y. 340; Clapp v. Fullerton, 34 N. Y. 190, 195, 90 Am. Dec. 681; O'Brien v. People, 36 N. Y. 276, 282; Van Pelt v. Van Pelt, 30 Barb. (N. Y.) 134, 141; Gehrke v. State, 13 Tex. 568. Compare: State v. Pike, 49 N. H. 399, 6 Am. Rep. 533; Delafield v. Parish, 25 N. Y. 9, 37, 38.

Contra: Hardy v. Merrill, 56 N. H. 227, 22 Am. Rep. 441.

48 See, post, §§ 380-382, as to opinion evidence of subscribing witnesses.

See, post, §§ 376-379, as to opinion evidence of expert witnesses. See, post, §§ 383-388, as to lay witnesses testifying to their opinions.

49 Murphy v. Murphy, 24 Mo. 526. See, also, Fry v. Morrison, 159 Ill, 244, 42 N. E. 774.

not know the contents of the instrument,50 and unless the law requires publication or acknowledgment by the testator of the instrument as his will, the witness may not know the nature of the document.51 It is said, however, that it is the duty of an attesting witness to judge of the testator's mental capacity as well as to protect him against fraud in the execution of his will.52 Even where the subscribing witnesses relied upon the declarations of another as to the mental condition of the testator, it has been said that such was not sufficient evidence to justify them in putting their names to the will as witnesses, and that it was in fact a fraud upon those whose rights were affected thereby.53 The weight of authority is that no person is justified in attesting a will unless he knows from the testator himself that the tes

50 Leverett's Heirs v. Carlisle, 19 Ala. 80; Turner v. Cook, 36 Ind. 129, 136; In re Higdon's Will, 6 J. J. Marsh (29 Ky.) 444, 22 Am. Dec. 84; Roche v. Nason, 105 App. Div. (N. Y.) 256, 93 N. Y. Supp. 565; In re Baker's Appeal, 107 Pa. St. 381, 52 Am. Rep. 478.

51 Gould v. Chicago Theological Seminary, 189 Ill. 282, 59 N. E. 536; Savage v. Bulger, 25 Ky. Law Rep. 763, 76 S. W. 361; Skinner v. American Bible Soc., 92 Wis. 209, 65 N. W. 1037.

52 "It is the duty of subscribing witnesses to inform themselves of the testator's mental capacity before attesting the will. Witnesses are required by the law not alone to protect the testator against fraud in the execution of his will, but also to judge of his capacity,

which is primarily established by their oaths when the will is offered for probate; but it will be presumed, until the contrary is shown, that they have discharged their duty."-Jones v. Collins, 94 Md. 403, 51 Atl. 398.

But compare Williams v. Lee, 47 Md. 321, where two surviving attesting witnesses, one of whom had prepared a codicil to the will which was offered for probate with it, testified that the testatrix was incompetent at the date of the execution of her will and the codici in question. The circumstances of the case, however, were satisfactorily explained, they being merely to humor the follies of an unbalanced mind.

53 Scribner v. Crane, 2 Paige (N. Y.) 147, 21 Am. Dec. 81.

tator understands what he is doing, and unless the witness is satisfied in his own mind as to the testator's mental capacity. A person, signing his name as a witness to a will, by his act of attestation vouches for the sanity of the testator.54 And if a subscribing witness thereafter attempts to give testimony discrediting the mental capacity of the testator, such evidence should be received with caution and closely scrutinized.55 The circumstances of the case, however, may cause the rule to relax.56 And in some decisions it is held that no inference can be drawn from the mere fact that a person sub

54 In re Tyler's Estate, 121 Cal. 405, 413, 53 Pac. 928; In re Nelson's Estate, 132 Cal. 182, 183, 64 Pac. 294; In re Motz's Estate, 136 Cal. 558, 69 Pac. 294; In re Field's Appeal, 36 Conn. 277; Withinton v. Withinton, 7 Mo. 589; Southworth v. Southworth, 173 Mo. 59, 73, 73 S. W. 129; Hughes v. Rader, 183 Mo. 630, 702, 82 S. W. 32; Thomasson v. Hunt, (Mo.) 185 S. W. 165; Heyward v. Hazard, 1 Bay. (S. C.) 335; Young v. Barner, 27 Grat. (Va.) 96.

"By placing his name to the instrument the witness, in effect, certifies to his knowledge of the mental capacity of the testator; and that the will was executed by him freely and understandingly, with a full knowledge of its contents. Such is the legal effect of the signature of the witness when he is dead or out of the jurisdiction of the court."-Scribner v. Crane, 2 Paige (N. Y.) 147, 21 Am. Dec. 81.

55 In re Nelson's Estate, 132 Cal. 182, 183, 64 Pac. 294; Thomasson v. Hunt, (Mo.) 185 S. W. 165; Young v. Barner, 27 Grat. (Va.) 96; In re Lewis' Will, 51 Wis. 101, 7 N. W. 829; Loughney v. Loughney, 87 Wis. 92, 58 N. W. 250.

"When a witness who has solemnly subscribed his name to a will as an attesting witness, knowing the nature of his act, and that deceased would rely upon his name as a part of the execution of the will, undertakes by his evidence to overthrow or cast suspicion upon it, his evidence should be closely scrutinized." — In re Motz's Estate, 136 Cal. 558, 69 Pac. 294, citing In re Tyler's Estate, 121 Cal. 405, 413, 53 Pac. 928.

56 "This rule, though just in its general application, ought not to be vigorously applied to a case like this, when the circumstances clearly show that the witnesses were suddenly called on and, with a haste dictated by the author and propounder of the paper, which

scribed his name as a witness to a will, and that by such act he does not express a silent belief that the testator is of sound mind.57

§ 376. Opinions of Medical Experts Admissible.

An exception to the general rule that a witness must testify only as to facts within his own knowledge and not express merely his belief, is that an expert, one having a special knowledge of the matter in controversy, may give his opinion. A medical expert, one who by study and experience is familiar with the symptoms of mental disorders, may, by stating his belief, assist the court or jury in arriving at a correct conclusion. The opinion of such

left them no time for due deliberation; and when called upon to testify, as they were, in behalf of the propounder, they were in duty bound to detail truly the facts and circumstances, in doing which they offered the only available and reliable data from which to draw proper judicial conclusions. They do not, therefore, strictly speaking, occupy the attitude of subscribing witnesses seeking to invalidate the will, but rather that of such witnesses disclosing the circumstances which led them to act inadvertently, and the facts touching and incident thereto."-Tucker v. Sandidge, 85 Va. 546, 571, 8 S. E. 650.

57 In Baxter v. Abbott, 7 Gray (Mass.) 71, the court says: "The fact that he attested the will as a witness does not, we think, furnish evidence of any opinion he had as to the sanity of the tes

tator. He may have had no opinion on the subject. He may have attested the will with the full belief that the testator was insane, and with the view of testifying to that opinion whenever the will should be offered for probate. No inference as to his opinion can be drawn from the mere fact of signing; and therefore evidence of a contradictory opinion expressed by him was, inadmissible."

Strangers frequently execute wills when they are unknown to the subscribing witnesses. By ac cepting an introduction by name, and by signing such name to his will, the testator acknowledges his identity. This is ordinarily sufficient unless identity is made a special issue by the pleadings.Harris v. Martin, 150 N. C. 367, 17 Ann. Cas. 685, 21 L. R. A. (N. S.) 531, 64 S. E. 126.

an expert may be based on facts within his personal knowledge, or be an answer to a hypothetical question based on the testimony of others.58 The opinion can not be asked on hypothetical facts not in evidence in the case. 59 The force and weight of such opinion must necessarily depend upon the truth or falsity of the facts embodied in the question. If the facts are erroneously assumed, or determined to be untrue, the opinion of the expert that the testator was insane would not destroy the presumption of testamentary capacity."

§ 377. Who Are Medical Experts.

The general rule is that a practicing physician may give his opinion regarding insanity without having made a specialty of such subject.1 But a physician who has devoted his time to some other branch of the profession

58 In re Overpeck's Will, 144 Iowa 400, 120 N. W. 1044, 122 N. W. 928; In re Eveleth's Will, (Iowa) 157 N. W. 257; Crockett v. Davis, 81 Md. 134, 149, 31 Atl. 710; Jones v. Collins, 94 Md. 403, 51 Atl. 398; May v. Bradlee, 127 Mass. 414; Kempsey v. McGinniss, 21 Mich. 123; Rice v. Rice, 50 Mich. 448, 15 N. W. 545.

Books on medical science or insanity, if objected to, can not be read in evidence. - McNaghten's Case, 10 Cl. & Fin. 200; Ware v. Ware, 8 Greenl. (Me.) 42; Davis v. State, 38 Md. 15; Commonwealth v. Sturtivant, 117 Mass. 122, 19 Am. Rep. 401.

59 Harrison v. Rowan, 3 Wash. C. C. 580, 587, Fed. Cas. No. 6141; Duffield v. Robeson, 2 Har. (Del.)

375, 385; Potts v. House, 6 Ga. 324, 50 Am. Dec. 329; Hurst v. Chicago, Rock Island & P. R. Co., 49 Iowa 76, 79; In re Ames, 51 Iowa 596, 2 N. W. 408; Commonwealth v. Rich, 14 Gray (Mass.) 335; Gibson v. Gibson, 9 Yerg. (17 Tenn.) 329.

60 Philips v. Philips, 77 App. Div. (N. Y.) 113, 78 N. Y. Supp. 1001.

61 Davis v. United States, 165 U. S. 373, 41 L. Ed. 750, 17 Sup. Ct. 360; Porter v. State, 140 Ala. 87, 37 So. 81; Matter of Mullin's Estate, 110 Cal. 252, 42 Pac. 645; People v. Sowell, 145 Cal. 292, 78 Pac. 717; In re Barber's Appeal, 63 Conn. 393, 22 L. R. A. 90, 27 Atl. 973; Taylor v. State, 83 Ga. 647, 10 S. E. 442; Schneider v.