Barney v. Latham was a United States Supreme Court case that dealt with the issue of whether a contract between two parties was valid. The case involved a contract between William Barney and William Latham, in which Barney agreed to pay Latham a certain amount of money for the use of a certain piece of land. Latham had previously sold the land to another party, and Barney argued that the contract was invalid because Latham did not have the right to sell the land. The Supreme Court held that the contract was valid, and that Latham had the right to sell the land. The Court reasoned that Latham had the right to sell the land because he had been in possession of it for a long period of time, and had made improvements to it. The Court also noted that Barney had knowledge of the fact that Latham had sold the land to another party, and that he had still agreed to the contract. Therefore, the Court held that the contract was valid and enforceable.

Justice Field delivered the dissenting opinion in Barney v. Latham, arguing that the majority's decision was contrary to both law and justice. He argued that under California state law, a married woman had an absolute right to her separate property regardless of any agreement between her and her husband. The Court should not have interfered with this right by allowing a third party - in this case, Latham - to take advantage of it for his own benefit. Furthermore, Justice Field noted that even if there were some ambiguity as to whether or not Mrs. Barney had waived her rights under California law when she signed the deed transferring title of certain real estate from herself and husband jointly into Mr. Barney’s name alone, such ambiguity should be resolved against Latham who took no steps whatsoever before purchasing said land from Mr. Barney other than relying on its record title which showed only one owner – namely Mr. Barney himself – without making any inquiry as to Mrs..Barney’s interest therein or obtaining any assurance thereof from either party prior thereto; thus he could not now be heard complaining about lack of knowledge regarding same at time he purchased said land from Mr..Barney alone