Dalton v. Jennings was a United States Supreme Court case that addressed the issue of whether a state court could enforce a contract that was made in violation of a state statute. The case involved a contract between two parties, Dalton and Jennings, in which Dalton agreed to pay Jennings a certain amount of money for a piece of land. The contract was made in violation of a state statute that prohibited the sale of land without a license. The state court ruled in favor of Jennings, finding that the contract was valid and enforceable. The Supreme Court reversed the decision of the state court, holding that the contract was void and unenforceable. The Court reasoned that the state statute was a valid exercise of the state's police power and that the contract was in violation of the statute. The Court further held that the state court could not enforce a contract that was made in violation of a state statute. The Court concluded that the contract was void and unenforceable and that the state court could not enforce it.

Justice Field delivered the dissenting opinion in Dalton v. Jennings, arguing that the majority's decision was contrary to both precedent and reason. He argued that a contract is not necessarily void if it violates public policy, as long as its purpose does not conflict with any law or statute of the state. Furthermore, he noted that even if such contracts are deemed invalid by courts of equity, they may still be enforced at common law depending on their circumstances. In this case specifically, Justice Field argued that there was no evidence presented to suggest that either party had acted fraudulently or maliciously in entering into the contract; thus it should have been upheld by the court despite being against public policy. Ultimately he concluded his dissent by stating "the conclusion reached by [the majority] is one which I cannot concur."