Smith & Griggs Manufacturing Company v. Sprague is a United States Supreme Court case that was decided in 1887. The case involved a dispute between Smith & Griggs Manufacturing Company and Sprague over a contract for the sale of a steam engine. Smith & Griggs had agreed to sell the engine to Sprague, but Sprague refused to pay the full amount due. Smith & Griggs then sued Sprague for breach of contract. The Supreme Court held that Sprague was liable for breach of contract. The Court found that the contract between the parties was valid and enforceable, and that Sprague had breached the contract by refusing to pay the full amount due. The Court also held that Smith & Griggs was entitled to damages for the breach of contract. The Court's decision in this case established the principle that a party who breaches a contract is liable for damages. This principle has been applied in numerous cases since then, and is still an important part of contract law today.

In Smith & Griggs Manufacturing Company v. Sprague, the Supreme Court was tasked with determining whether a contract between two parties could be enforced when it had been made in violation of a state statute. The majority opinion held that the contract was not enforceable due to its illegality under state law and thus dismissed the case. Justice Field dissented from this decision, arguing that while contracts which are illegal on their face should not be enforced, those which merely violate an existing statute should still be upheld if they do not conflict with public policy or morals. He further argued that since there were no such issues present in this particular case, then it would have been appropriate for the court to uphold the agreement between Smith & Griggs and Sprague as valid and binding upon both parties despite its technical illegality under state law.