The Duncan Townsite Company v. Lane, Secretary of the Interior case in 1917 revolved around a dispute over land ownership rights. The Duncan Townsite Company claimed that it had purchased certain lands from the United States government under an act passed by Congress in 1891 which allowed for such sales to be made to townships and cities for public purposes. However, these lands were also part of an Indian reservation established by executive order in 1908. The Supreme Court ruled against the Duncan Townsite Company stating that while Congress did have authority to sell off public lands, this power was not absolute and could not infringe upon existing rights or reservations held by Native American tribes unless explicitly stated otherwise within legislation itself. Therefore, since no explicit provision was made within the Act of 1891 regarding sale of reservation land, any purchase made under its provisions would not include such territories.

In the dissenting opinion for Duncan Townsite Company v. Lane, it was argued that the majority's decision to uphold a ruling by the Secretary of Interior which denied Duncan Townsite Company's claim to certain lands in Oklahoma was incorrect. The dissenting justices believed that under federal law at the time, when an Indian tribe ceded its land rights to the U.S., those lands became public and subject to settlement laws including townsite laws. They contended that this made it possible for townsites like Duncan Townsite Company to lay claim on such lands even before they were officially opened up for settlement by proclamation of President Roosevelt in 1901. Furthermore, they disagreed with majority’s interpretation of Section 16 of Curtis Act (1898) as not allowing townsites claims prior opening up these lands; instead arguing that this section only required approval from Secretary of Interior but did not prohibit such claims outrightly.