In the case of Johnson v. Lankford et al., 1917, the US Supreme Court ruled on a dispute over land ownership in Oklahoma. The plaintiff, Johnson, claimed that he had purchased a tract of land from an individual who was part Native American and therefore exempt from certain restrictions on selling their allotted lands without government approval. However, after his purchase, another party (Lankford) also claimed ownership of the same property based on a previous sale by the same seller which had been approved by federal authorities. The lower court sided with Lankford and this decision was upheld upon appeal to the Supreme Court. The key issue at stake revolved around whether or not sales made by Native Americans without governmental consent were valid under law - specifically Section Sixteen of an Act passed in 1902 regarding tribal allotments in Oklahoma Territory. In its ruling for Lankford et al., the Supreme Court held that such sales were indeed invalid unless they received official sanction as required under existing legislation. This case thus reinforced legal protections for indigenous peoples' rights to control their own property while also highlighting potential pitfalls associated with purchasing real estate where clear title may be difficult to establish due to historical factors.

In the dissenting opinion for Johnson v. Lankford, it was argued that the majority's decision to uphold Oklahoma's Grandfather Clause - a law designed to disenfranchise African American voters - was fundamentally flawed and unconstitutional. The dissenting justices contended that this clause violated both the Fourteenth and Fifteenth Amendments of the Constitution by imposing unfair literacy tests on black citizens while exempting white citizens from these same requirements based on their ancestral voting history. They believed that such racial discrimination in voting rights is not only morally wrong but also legally indefensible under U.S constitutional law, which guarantees equal protection under the law and prohibits any state from denying or abridging a citizen’s right to vote "on account of race, color, or previous condition of servitude." Therefore, they strongly disagreed with the majority's ruling in favor of upholding this racially discriminatory legislation.