Question: When did the U.S. Supreme Court resolve a longstanding dispute regarding the border between Texas and Louisiana?
Answer: March 20, 1973. In Texas v. Louisiana, the Court confirmed that the disputed boundary between the two states was the geographic middle of the Sabine River, not its western bank or the middle of its navigable channel, as Louisiana claimed. The Sabine River’s western bank was established as the boundary between the United States and Spain in the 1819 Adams-Onis Treaty and confirmed by the 1838 Convention of Limits, the aforementioned agreement between the U.S. and Republic of Texas.
After Texas was admitted to the Union in 1845, Congress concurred with an 1848 resolution to extend the state’s boundary to the middle of the river. The Supreme Court’s 1973 decision confirmed this boundary and its application to the islands on either side of it.
