In the Knight v. United States Land Association case of 1891, the Supreme Court dealt with a dispute over land ownership in California. The plaintiff, Knight, claimed that he had purchased a piece of property from an individual who had received it as part of a Mexican land grant before California became part of the U.S., and therefore his claim was valid under the Treaty of Guadalupe Hidalgo which ended the Mexican-American War. However, this claim conflicted with another made by defendants (United States Land Association) who argued they owned rights to same parcel through purchase from federal government after statehood. The court ruled in favor of United States Land Association stating that when California became a state, all unappropriated or vacant lands automatically passed into possession and control of Federal Government regardless any prior Spanish or Mexican grants unless such claims were presented and validated within two years after treaty ratification - something not done by original owner from whom Knight bought his title.

In the dissenting opinion for Knight v. United States Land Association, Justice Lamar disagreed with the majority's interpretation of the Swamp Land Act of 1850. He argued that this act was intended to grant swamp and overflowed lands to states so they could fund improvements such as drainage systems, not simply to transfer ownership from federal government to state governments. Therefore, he believed that California had a valid claim on these lands even if it did not formally accept them until after private parties like Knight had purchased them from the federal government. Furthermore, he contended that since Congress never explicitly repealed or amended this provision in subsequent legislation related to public land sales, its intent should still govern how these cases are decided. Thus, according to Justice Lamar’s view, Knight's purchase should be considered invalid because it conflicted with California's prior rights under the Swamp Land Act.