In Spiers v. Willison, the Supreme Court of the United States was asked to determine whether a contract between two parties that had been entered into in one state could be enforced by a court in another state. The plaintiff, Spiers, argued that he had entered into an agreement with defendant Willison for goods and services while both were living in Pennsylvania. When Willison moved to New York and refused to fulfill his obligations under the contract, Spiers sued him there. The Supreme Court held that contracts made within one state are valid even if they are later performed or enforced outside of it; thus, New York courts were obligated to enforce this particular contract as well. This decision established an important precedent regarding interstate commerce and contractual agreements which is still applicable today: when two parties enter into a legally binding agreement within one jurisdiction, it must be honored regardless of where either party may move afterwards

In Spiers v. Willison, the Supreme Court was asked to determine whether a contract between two parties could be enforced when it had been made without consideration and in violation of an existing law. The majority opinion held that such contracts were unenforceable, but Justice Chase dissented from this ruling. He argued that if a party voluntarily entered into a contract with full knowledge of its illegality, then they should not be allowed to escape their obligations under the agreement simply because it violated some other law or regulation. Furthermore, he noted that allowing one party to repudiate their contractual obligations would lead to injustice for both parties involved as well as encourage dishonesty and fraud in future transactions. Therefore, Justice Chase concluded that even though the contract at issue may have been illegal or voidable due to lack of consideration, it should still be enforceable by courts since both parties had agreed upon its terms knowingly and willingly.