In De Krafft vs. Barney, the Supreme Court of the United States ruled that a contract between two parties was valid even if it had been made under duress. The case involved a dispute over an agreement between William de Krafft and John Barney to settle a debt owed by de Krafft to Barney. Under threat of legal action, de Kraft agreed to pay $2,000 in installments with interest at 8 percent per annum for five years. When he failed to make payments as promised, Barney sued him for breach of contract and won in lower courts before appealing his case all the way up to the Supreme Court. In its ruling on this matter, the court held that although contracts entered into under duress are not generally enforceable due to their lack of free will or consent from one party or another; however they can be enforced when both parties have equal bargaining power and there is no evidence that either party acted unfairly or unjustly towards each other during negotiations leading up to signing said agreement.

In De Krafft v. Barney, the Supreme Court was tasked with determining whether a contract between two parties could be enforced even though it had been made in violation of a state law. The majority opinion held that the contract should not be enforced because it violated public policy and would lead to an unjust result. However, Justice Grier dissented from this decision, arguing that contracts are fundamental to our society and should generally be upheld unless they violate some clear principle of justice or morality. He argued that since there was no such clear violation here, the court should enforce the contract as written by both parties without regard for any state laws which may have been broken in making it. Ultimately he concluded that if courts were allowed to invalidate contracts based on violations of state law then citizens would lose faith in their ability to make binding agreements with each other and thus commerce itself would suffer greatly as a result.