Opinion Testimony of Medical Experts Regarding Mental Capacity In Michigan
Opinion testimony of medical experts regarding testamentary capacity is not accorded superior status with respect to lay testimony under Michigan law.
In In re Estate of Moxon, 234 Mich 170, 173-174; 207 NW 924 (1926), the Supreme Court of Michigan held that any witness, lay or expert, who has knowledge about whether a testator had the necessary mental capacity to execute a will is permitted to testify.
Similarly, in In re Searchill Estate, 9 Mich App 614, 622; 157 NW2d 788 (1968), this Court held that a lay witness may give testimony on the question of the competency of a testator where a foundation is laid and an opportunity is given for cross-examination.
In In re Estate of Lewandowski, 236 Mich 136; 210 NW 314 (1926), the Court held that opinion testimony of professional witnesses was competent as to what extent the testatrix's mind was affected by the disease with which she was afflicted, her mental condition shortly before her will was executed, and the possibility of her regaining consciousness within that time.
However, in Bradford v. Vinton, 59 Mich 139, 154; 26 NW 401 (1886), the Court stated:
The opinion of a physician as to mental competency, aside from the question of insanity, is entitled to no greater consideration than that of a layman, having equal facilities for observation. . . . the weight which should have been given to the testimony was for the jury, and whether the testimony of the physician upon the question of mental capacity or competency should be given greater or less weight than that of laymen upon the same question was exclusively for them to decide.