A review of our cases reveals that, in the main, we have stated that undue influence such as to vitiate a will must be proved by a preponderance of the evidence. Spinar v. Wall, 191 Neb. 395, 215 N.W.2d 98 (1974); Cook v. Ketchmark, 174 Neb. 222, 117 N.W.2d 375 (1962); Benge v. Sutton, 169 Neb. 769, 100 N.W.2d 857 (1960); Buchanan v. Zorn, 169 Neb. 396, 99 N.W.2d 773 (1959); Reynolds v. Knott, 164 Neb. 365, 82 N.W.2d 568 (1957); In re Estate of Fehrenkamp, 154 Neb. 488, 48 N.W.2d 421 (1951); In re Estate of Thompson, 153 Neb. 375, 44 N.W.2d 814 (1950); In re Estate of Farr, 150 Neb. 67, 33 N.W.2d 454 (1948), on rehearing 150 Neb. 615, 35 N.W.2d 489 (1949). We have, however, on at least one occasion aberrantly said that such proof must be by clear and convincing evidence.
See In re Estate of Barger , 303 Neb. 817, 931 N.W.2d 660 (2019). See, also, Spinar v. Wall , 191 Neb. 395, 215 N.W.2d 98 (1974). Because undue influence is often difficult to prove with direct evidence, it may be reasonably inferred from the facts and circumstances surrounding the actor: his or her life, character, and mental condition. In re Estate of Barger, supra . Mere suspicion, surmise, or conjecture does not warrant a finding of undue influence; instead, there must be a solid foundation of established facts on which to rest the inference of its existence.
See In re Estate of Barger, 303 Neb. 817, 931 N.W.2d 660 (2019). See, also. Spinar v. Wall, 191 Neb. 395, 215 N.W.2d 98 (1974).
See, e.g., In re Estate of Hedke, 278 Neb. 727, 775 N.W.2d 13, 28 (2009); In re Estate of Novak, 235 Neb. 939, 458 N.W.2d 221, 224 (1990); In re Estate of Peterson, 232 Neb. 105, 439 N.W.2d 516, 520 (1989); In re Estate of Villwok, 226 Neb. 693, 413 N.W.2d 921, 924 (1987); In re Estate of Price, 223 Neb. 12, 388 N.W.2d 72, 79 (1986); In re Estate of Gloe, 191 Neb. 395, 215 N.W.2d 98, 101 (1974); In re Estate of Gorthy, 169 Neb. 769, 100 N.W.2d 857, 864 (1960); In re Bainbridge's Estate, 151 Neb. 142, 36 N.W.2d 625, 626 (1949); In re Bowman's Estate, 143 Neb. 440, 9 N.W.2d 801, 806 (1943). Notably, both Nebraska and South Dakota, like Iowa, employ a preponderance-of-the-evidence standard to undue influence claims in will contests when no fiduciary relationship is present.
No one claims that the trial judge invaded the jury's province by taking upon himself the decision of whether the 1977 will, less the devises and codicils found by the jury to be the product of undue influence, was valid. The procedure employed by the trial judge has been implicitly approved by us in Spinar v. Wall, 191 Neb. 395, 215 N.W.2d 98 (1974), and In re Estate of George, 144 Neb. 887, 15 N.W.2d 80 (1944). However, we have been directed to no case, and we find none, which specifically and directly holds that the issue of partial or total invalidity of a will containing void provisions is a question for the court. For the answer to this question we look at the rule of partial invalidity as adopted in Nebraska.
It is obvious that mental capacity and soundness of mind are relevant considerations in determining whether a testatrix is subject to undue influence, and cases have so stated. Spinar v. Wall, 191 Neb. 395, 215 N.W.2d 98 (1974); In re Estate of Paisley, 91 Neb. 139, 135 N.W. 435 (1912); 79 Am. Jur. 2d, Wills, 396, p. 554. Thus in will contests where the testatrix has diminished mental capacity, the issues of both competency and undue influence often arise, and it is proper to submit both issues to the jury for a finding of fact.
Implicit in the concept of undue influence, as that term is used in the law, is the premise that the influence which overcomes the will of the testator must be undue influence exercised upon the testator by someone else so that the testamentary disposition is not really the testator's own. See, Scholting v. Scholting, 183 Neb. 850, 164 N.W.2d 918; Spinar v. Wall, 191 Neb. 395, 215 N.W.2d 98. Neither this court nor any other that we know of has equated an uninfluenced motive of the testator with undue influence.