In the 1906 case of United States ex rel. West v. Hitchcock, the U.S Supreme Court dealt with a dispute over land rights in Oklahoma between Native American tribes and non-Native settlers. The plaintiff, West, claimed that certain lands were reserved for public use under an agreement made with the Creek Nation in 1866 and therefore could not be allotted to individual tribe members or sold to non-Natives. However, Secretary of Interior Ethan A. Hitchcock interpreted this agreement differently; he believed it allowed for allotment and sale after all tribal members had received their shares. The court sided with Hitchcock's interpretation by ruling that Congress had plenary power over Indian affairs - meaning they have full and complete authority to regulate all matters concerning Native Americans including property issues - thus allowing them to interpret treaties as they see fit without judicial review unless there is clear evidence of mistake or fraud involved. This decision affirmed federal control over tribal lands while also setting a precedent for future cases involving treaty interpretations: courts would defer to congressional intent unless there was compelling reason not to do so.

In the dissenting opinion for United States ex rel. West v. Hitchcock, Justice Harlan argued that the majority's decision was a gross violation of Native American rights and an overreach of executive power. He contended that once Congress had set aside lands as reservations for Native Americans, those lands could not be taken away or reduced without congressional approval - something he believed did not occur in this case. Furthermore, he pointed out that the President's proclamation reducing reservation land contradicted previous treaties with Native American tribes which guaranteed their right to these territories "for all time". In his view, such unilateral action by the executive branch undermined both treaty obligations and Congressional authority.