The U.S. Supreme Court case Washington et al. v. Washington State Commercial Passenger Fishing Vessel Association et al., 1978, centered around the interpretation of fishing rights treaties signed in the mid-19th century between Native American tribes and the United States government. The court was asked to determine whether these treaties guaranteed tribes a specific portion of harvestable fish each year or merely granted them access to traditional fishing locations without any guarantee of catch quantity. In a landmark decision, the Supreme Court ruled that these treaties did indeed ensure tribal members were entitled to up to half of all harvestable fish from their usual and accustomed grounds each year, not just access as argued by non-Native fishermen's groups who brought forth this litigation due to declining salmon populations in Pacific Northwest waters. This ruling affirmed earlier decisions made by lower courts and established an important precedent for interpreting treaty rights with indigenous peoples across America - emphasizing that such agreements should be understood as they would have been comprehended by tribal leaders at signing time rather than through modern legalistic perspectives.

In the dissenting opinion for Washington v. Washington State Commercial Passenger Fishing Vessel Association, Justice William H. Rehnquist disagreed with the majority's interpretation of the 1855 treaty rights of Native American tribes in Washington state to fish "at all usual and accustomed grounds." He argued that these rights should not be interpreted as guaranteeing half of all harvestable fish to tribal members, but rather only a right to access traditional fishing locations without interference from non-tribal authorities. Furthermore, he contended that such an expansive reading would unfairly disadvantage non-tribal commercial fishermen who had built their livelihoods around these resources over many years under state regulation. Lastly, he expressed concern about judicial overreach and potential negative impacts on future negotiations between states and tribes if courts were seen as too willing to reinterpret historical treaties in favor of tribal interests.