In the United States v. Locke case of 1984, the Supreme Court ruled on a dispute over state versus federal authority in regulating certain aspects of mining operations on public lands. The State of California had imposed its own regulations regarding the filing and maintenance of mining claims that were more stringent than those set by Federal law under the Mining Act of 1872. Miners and landowners challenged these rules, arguing they conflicced with federal laws governing public lands. The Supreme Court held that while states have significant power to regulate activities within their borders, this does not extend to areas where Congress has established an overriding need for national uniformity such as management and disposal policies for public lands owned by all Americans. Therefore, California's additional requirements were pre-empted by Federal law because they stood 'as an obstacle to the accomplishment and execution'of full purposes and objectives embodied in it. This decision reaffirmed supremacy clause principles which dictate that when state law is in conflict with federal law, federal law prevails.

In the dissenting opinion for United States v. Locke, Justice Thurgood Marshall argued that the majority's decision to uphold a California law requiring mineral claimants on federal lands to file annual statements of labor performed was an overreach of state power. He contended that this ruling contradicted previous Supreme Court decisions which had held that states could not impose additional requirements on federal land users beyond those set by Congress. Furthermore, he expressed concern about potential negative impacts on individual property rights and economic interests, as well as possible future conflicts between state and federal laws governing public lands use. Ultimately, Justice Marshall believed the majority's decision undermined both Congressional authority and established legal precedent regarding control over federally-owned resources.