Such actions are improper. A contract entered into under duress by physical compulsion is void. Moreover, "if a party’s manifestation of assent to contract is induced by an improper threat by the other party that leaves the victim no reasonable alternative, the contract is voidable by the victim."
Very frequently, the question of duress happens when courts are asked to rule on the enforceability of prenuptial agreements. In order for a court to enforce a prenuptial agreement, the parties must have entered into it voluntarily. In other words, the courts must know that the agreement was signed without duress, with "full opportunity to review the agreement with counsel..."
As a defense in civil action, duress must be pleaded affirmatively. Sometimes in divorce actions the parties make affirmative defenses, which are new facts or legal defenses in response to the opposing spouse’s pleading. In a pleading, an affirmative defense is a response, which assuming the complaint is true, constitutes a defense to it. An affirmative defense provides an explanation and justification that must be pleaded in an answer, accord or satisfaction. Assumption of risk, duress, coercion, and estoppel are examples of affirmative defenses.
Duress is also a common ground for an annulment. No one may force another person into marriage.