It is not infrequently stated as the reason why an instrument obtained under duress may be avoided, that the duress has deprived the person subjected to it of the capacity to consent, and that any writing which he may have signed is not in fact his contract,92 though courts making such statements would not be likely to carry them to their logical conclusion. If they did they would hold void every instrument obtained under duress. It could not be ratified and could only have effect in favor of innocent third persons where an estoppel could be proved. It could make no difference whether the means of coercion were rightful or wrongful. The only inquiry would relate to contractual capacity. The truth of the situation, however, is expressed by Holmes, J.:93 "Duress, like fraud, rarely, if ever, becomes material as such, except on the footing that a contract or conveyance has been made which the party wishes to avoid. It is well settled that where, as usual, the so-called duress consists only of threats, the contract is only voidable.94
"This rule necessarily excludes from the common law the often recurring notion just referred to, and much debated by the civilians, that an act done under compulsion is not an act in a legal sense. Tamen coactus volui." 95 It follows that only the party suffering from duress can set it up. Neither the party exercising coercion,96 nor third persons 97 can do so. Fur-
92 In Wilson v. Calhoun, 170 Iowa, 111, 120, 151 N. W. 1087, it was said: "It is of no consequence that the parties guilty of the duress or undue influence received no benefit therefrom. A trust deed which is obtained by duress or undue influence is void although neither the trustee nor the beneficiaries participated therein. The reason for this is that the instrument is not the deed of the party making it and is avoidable at his election. Ewing v. Bass, 149 Ind. 1, 48 N. E. 241; First Nat. Bank v. Bryan, 62 Iowa, 42, 17 N. W. 166; Smith v. Boyd, 61 N. J. Eq. 175, 47 Atl. 816; City Nat. Bank v. Kusworm, 88 Wis. 188, 59 N. W. 564, 26 L. R. A. 48, 43 Am. St. Rep. 880,
91 Wis. 166, 64 N. W. 843." See also Baker ». Morton, 12 Wall. 150, 20 L. Ed. 262.
93 Fairbanks v. Snow, 145 Mass. 153, 154, 13 N. E. 596,1 Am. St. Rep. 446. See also Royal v. Goss, 154 Ala. 117, 45 So. 231.
94 Citing Foss v. Hildreth, 10 Allen, 76, 80; Vinton v. King, 4 Allen, 562, 565; Lewis v. Bannister, 16 Gray, 500; Fisher v. Shattuck, 17 Pick. 252; Worcester v. Eaton, 13 Mass. 371, 375, 7 Am. Dec. 155; Whelpdale's Case, 5 Rep. 119a, 1 Bl. Com. 130.
95 Citing Dig. 4, 2, 21, Sec. 5; 1 Wind-scheid, Pandekten, Sec. 80.
96 Supra, Sec. 1623, n. 88.
97 Schmidt v. Gaukler, 156 Mich. 243, ther if a formal instrument is made under duress in violation of a previous agreement or understanding, the grantor cannot set up rights varying from those set out in the instrument without first having it reformed in an equitable proceeding.98