A relationship between parties to a transaction which tends to give one dominance over the other may be an important element in determining whether duress was exercised. And courts of equity have established the principle that when such a relation exists, the burden is thrown upon the dominant party to
6Meek v. McClure, 49 Gal. 623; Jenks v. lima Township, 17 Ind. 326; Howard v. Augusta, 74 Me. 79; Boston & Sandwich Glass Co. v. Boston, 4 Mete. (Mass.) 181; Cox v. Welcher, 68 Mich. 263, 36 N. W. 69, 13 Am. St. Rep. 339; DeGraff v. Ramsey County, 46 Minn. 319, 48 N. W. 1135.
7 See Yates v. Royal Ins. Co., 200 111. 202, 65 N. E. 726.
8 Herold v. Kahn, 159 Fed. 608, 612, 86 C. C. A. 598; Cambria Steel Co. v. McCoach, 225 Fed. 278.
9 See Wheatland v. Boston, 202 Mass. 258, 88 N. E. 769.
10 In Maskell v. Horner,  3 K. B. 106, the defendant demanded and received from 1900 to 1912 certain market tolls to which, it was held in the latter year, he had no right. In a suit to recover the payments, it was said by the court in answer to the contention that they were voluntary: "It is clear, and was indeed admitted at the Bar, that no express words are necessary and that the circumstances attending the payments and the conduct of the plaintiff when making them may be a sufficient indication to the defendant that the payments were not made with the intention of closing the transactions. I do not think that the mere fact of a payment under protest would be sufficient to entitle the plaintiff to succeed; but I think that it affords some evidence, when accompanied by other circumstances, that the payment was not voluntarily made to end the matter. . . ."
"During the long period of years whenever the plaintiff challenged the defendant's right, there was a seizure or a threat of seizure of the plaintiff's goods. A threat intended to be followed by seizure is equivalent for this purpose to a seizure. (See per Cress-well, J., in Valpy v. Manley, 1 C. B. 594, 606.) . . "
"I cannot think that the protests lost their effectiveness by reason of the length of period during which they were persistently made, or because they establish the fairness of the transaction and that it was a free act of the other party. This principle has been generally applied to cases of settlements of property especially gifts, rather than to contracts, but does not seem confined to such cases. It is applied where a parent obtains a conveyance from a child;11 and also where a child has obtained a conveyance from an aged parent by means of an agreement to support.12 So an advantage obtained by a husband from a wife;13 or by one who stands in the position of a guardian from a ward, whether legal guardianship exists or not,14 or by an attorney from a client,15 a were at times accompanied by a laugh or jest. The persistence during so long a period serves rather to show that the plaintiff would not acquiesce in the defendant's demands."
11 Savery v. King, 5 H. L. Cas. 627; Powell v. Powell,  1 Ch. 243; Hassell v. Hassell, (Ala. 1918), 77 So. 716; Sayles v. Christie, 187 111. 420, 58 N. E. 480; Ferns v. Chapman, 211 111. 597, 71 N. E. 1106; Couchman's Admr. v. Couchman, 98 Ky. 109,32 S. W. 283; Wiley v. Wiley, 178 Ky. 501, 199 S. W. 47; Ashton v. Thompson, 32 Minn. 25, 18 N. W. 918; Davis v. Strange's Exr., 86 Va. 793,11S. E. 406, 8 L. R. A. 261.
12 Williams v. Langwill, 241 111. 441, 89 N. E. 642,25 L. R. A. (N. S.) 932n; Mott v. Mott, 49 N. J. Eq. 192, 22 Atl. 997. Cf. Stanfill v. Johnson, 159 Ala. 546, 49 So. 223.
13Harraway v. Harraway, 136 Ala. 499, 34 So. 836; White v. Warren, 120 Cal. 322, 49 Pac, 129, 52 Pac. 723; Stenger Assn. v. Stenger, 54 Neb. 427, 74 N. W. 846; Hall v. Otterson, 52 N. J. Eq. 522, 28 Atl. 907.
14 Smith v. Kay, 7 H. L. Cas. 750; Noble's Adm. v. Moses, 81 Ala. 530, 1 So. 217, 60 Am. Rep. 175; Albrecht v. Hunecke, 196 111. 127, 63 N. E. 616.
15 Gibson v. Jeyes, 6 Ves. 266; Savery v. King, 5 H. L. Cas. 627; White v. Tolliver, 110 Ala. 300, 20 So. 97; Klein v. Borchert, 89 Minn. 377, 95 N. W. 215; Dunn v. Dunn, 42 N. J. Eq. 431, 7 Atl. 842; Wistar's Appeal, 54
Pa. St. 60; Unruh v. Lukens, 166 Pa. St. 324, 31 Atl. 110.
In Ridge v. Healy, 251 Fed. 798,805, 164 C. C. A. 32, the court said: "1. A contract between attorney and client relative to compensation for services, made after the relationship has been entered into, is not per se void, but is presumptively invalid, and will be scrutinised very carefully by the courts whenever the transaction is called in question. Such a contract stands on the same basis as a contract between guardian and ward, or trustee and cestui que trust.
"2. The burden of proof is upon the attorney to show fairness and openness in the making of the contract, and that full information and explanation was given to the client, both of the facts, so far as known to the attorney, and also of her legal rights.
"3. Such a contract, in case of dispute as to the meaning of its terms, will be construed most strongly against the attorney.
"4. If the attorney comes into a court of equity, seeking the enforcement of such a contract, he must be prepared to show that such enforcement will not be unfair or inequitable to the client; in other words, that his claim, independent of the express terms of the contract, is so fair and equitable, that a court of equity would not hesitate to enforce it. Perry on Trusts (6th ed.), Sec.Sec. 202, 203; 1 Story, physician from a patient,16 a pastor from a parishioner,17 is subject to the same rule; which is indeed applicable to any relationship where one party is in a position to influence unduly the will of another.
Eq. Jur. (13th ed.), .Sec.Sec.310, 311; 3 Am. & Eng. Ency. of Law (2d ed.), pp. 332, 333; Elmore v. Johnson, 143 111. 513, 32 N. E. 413, 21 L, R. A. 366, 36 Am. St, Rep. 401; Tripe v. Corn-stock, 121 Fed. 620, 57 C. C. A. 646, 61 L. R. A. 176; United States v.. Coffin, 83 Fed. 337; French v, Cunningham, 149 Ind. 632, 49 N. E. 797; Nesbit v. Lockman, 34 N. Y. 167; Hitchings v. VanBrunt, 38 N. Y. 335; In re Holland, 110 N. Y. App. Div. 799, 97 N. Y, S. 202."
16 Dent v. Bennett, 4 Mylne & Cr. 269; Woodbury v. Woodbury, 141
Mass. 329, 5 N. E. 275, 55 Am. Rep. 479; Bogie v. Nolan, 96 Mo. 85, 9 8. W. 14; Unruh v. Lukens, 166 Pa. St. 324, 31 Atl. 110.
17 Huguenin v. Baseley, 14 Ves. Jr. 273; Allcard v. Skinner, 36 Ch. Div. 145; Morley v. Loughnan,  1 Ch. 736; Ross v. Conway, 92 Cal. 632, 28 Pac. 785; Good v. Zook, 116 Iowa, 582, 88 N. W. 376; Caspari v. First German Church, 82 Mo. 649; Corrigan v. Pironi, 48 N. J. Eq. 607, 23 Atl. 355; Marx v. McGlynn, 88 N. Y. 357; McClellan v. Grant, 83 N. Y. App. Div. 599, 82 N. Y. S. 208.