Plummer v. Sargent is a United States Supreme Court case that was decided in 1888. The case involved a dispute between two parties over the ownership of a piece of land in the state of Massachusetts. The plaintiff, Plummer, claimed that he had purchased the land from the defendant, Sargent, in 1876. Sargent, however, argued that he had never sold the land to Plummer and that he was still the rightful owner. The Supreme Court ultimately sided with Plummer, ruling that he had indeed purchased the land from Sargent in 1876. The Court found that Sargent had made a verbal agreement to sell the land to Plummer and that this agreement was binding. The Court also found that Sargent had accepted payment from Plummer for the land and that this was sufficient evidence to prove that the sale had taken place. The Court's decision in Plummer v. Sargent established that verbal agreements can be legally binding and that they can be used to prove the transfer of ownership of land. This decision has been cited in numerous subsequent cases and has become an important precedent in contract law.

Justice Field delivered the dissenting opinion in Plummer v. Sargent, arguing that the majority's decision was contrary to established precedent and would lead to a great deal of confusion for future cases. He argued that under existing law, an action could be brought against a public officer who had acted without authority or exceeded his powers; however, he noted that this case did not involve such circumstances as there were no allegations of fraud or bad faith on behalf of either party. Furthermore, Justice Field stated that it was well-established law at the time that when one party has been wrongfully deprived of their property by another due to some legal defect in title or possession, they are entitled to restitution from those responsible for causing such deprivation. In conclusion, Justice Field believed the Court should have followed prior decisions and allowed Sargent’s suit against Plummer since she had been wrongfully deprived her land through no fault of her own.