Ward v. Todd is a United States Supreme Court case that was decided in 1881. The case involved a dispute between two parties over a contract for the sale of a steamboat. The plaintiff, Ward, had contracted to purchase the steamboat from the defendant, Todd. Ward had paid a portion of the purchase price, but Todd refused to deliver the steamboat. Ward then brought suit against Todd for breach of contract. The Supreme Court held that the contract between Ward and Todd was valid and enforceable. The Court found that the contract was supported by consideration, meaning that both parties had given something of value in exchange for the steamboat. The Court also found that the contract was not void for lack of mutuality, meaning that both parties had agreed to the same terms. The Court ultimately held that Todd was liable for breach of contract and ordered him to deliver the steamboat to Ward. The Court also ordered Todd to pay damages to Ward for the breach. This case established the principle that contracts must be supported by consideration and mutuality in order to be enforceable.

Justice Field delivered the dissenting opinion in Ward v. Todd, arguing that the majority's decision was contrary to established precedent and would have a detrimental effect on commerce between states. He argued that while it is true that state laws can be preempted by federal law, this case did not involve any conflict between state and federal statutes or regulations. Instead, he contended that the issue at hand was whether a contract made under one state's laws could be enforced in another state without violating its public policy; Justice Field believed such contracts should generally be enforceable unless they are "injurious to society." Furthermore, he noted that if each individual state were allowed to determine which contracts from other states were valid within their own borders then interstate commerce would suffer greatly due to uncertainty over what agreements might ultimately be upheld or rejected. As such, Justice Field concluded his dissent by asserting there should only exist limited exceptions for when a contract made under one jurisdiction cannot be enforced in another based upon its public policy considerations.