The defendant was charged with the crime of murder, and was convicted of manslaughter. The defendant was himself shot by the deceased during the difficulty which resulted in the homicide, and it was a contested question upon the trial as to whether the defendant or the deceased fired first, the contention of the defendant being, that he acted in self-defense, and did not shoot until after he himself was wounded; and in the determination of this question it became material to ascertain the position in which the defendant was at the time when he was shot.
Upon the trial, Dr. Hayden, a physician and surgeon, was called as a witness on behalf of the people, and was asked: “ Will you state, if you can, from your examina*447tion of this man’s arm and your familiarity with gunshot-wounds, if you are familiar with them, in what position, in your judgment, this man’s arm was at the time that wound was received?” The question was objected to by defendant as incompetent, which objection was overruled, and the witness, in giving his opinion, stated that the defendant when shot was in one of two positions: 1. Standing with his side toward the discharged weapon, with the forearm flexed almost to a right angle to the upper arm, and the arm and elbow carried in front of and well toward the right side of the trunk, the trunk being inclined to the right of a perpendicular; or 2. “ The arm may have been only partially flexed in the upper arm, and hanging at the side, the wounded party having his back toward the party firing the shot”; but the general tenor of his testimony was to the effect that he inclined to the opinion that the wound was received while the defendant was in this latter position. The court erred in the admission of this evidence. The subject-matter of the inquiry was not one in relation to which the opinion of an expert can be properly received. The position of the wound being given, and the course taken by the bullet known, the jury was fully as competent to determine the relative positions of the parties to the difficulty as was the witness. (People v. Kennedy, 39 N. Y. 245; Cooper v. State, 23 Tex. 331; People v. Westlake, 62 Cal. 303.)
Nor can we agree with the attorney-general and associate counsel for the people, that the admission of this incompetent evidence was a harmless error, and therefore without prejudice to the appellant. It went to sustain the theory of the people in relation to the pivotal point in the case, and at the same time to discredit the testimony of the defendant. The defendant testified, in effect, that he did not draw his weapon or fire until after he had been shot by the deceased; that after firing the first time he continued to face the deceased, at the same time backing to and against the door, and while thus backing he shot at the deceased again. On the other *448hand, the theory of the prosecution seems to have been, that the defendant fired the first shot, and then turned and ran, and while running toward the door was shot by the deceased; and in this connection, Brown, a witness for "the people, who was present and engaged in the difficulty, and was himself knocked down by the defendant, testified: “I don’t know who drew his pistol first. I know that during the shooting Mr. Smith started to run, and ran fast. Q. Did he turn his back, or back out ? A. Turned his back.” If the testimony of this witness is true, then the deceased must have received his mortal wound before the defendant turned his back upon him and started to run away, and if the defendant was shot, as Dr. Hayden seemed to think more probable, while his arm was hanging down by his side and his back turned toward the deceased, the inference would be, that he was shot while running away in the manner described by the witness Brown, and that the testimony of the defendant, that he did not fire his weapon until after he was himself shot, was therefore untrue. In this state of the case, we do not think it can be said, with any certainty, that this incompetent evidence did not have an influence upon the minds of the jurors in reaching a verdict, and for the error in admitting it the judgment must be reversed.
Judgment and order are reversed.
Beatty, C. J., Harrison, J., and Sharpstein, J., concurred.