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Texas v. White, 74 U.S. (7 Wall.) 700 (1869), was a case argued before the United States Supreme Court in 1869
In accepting original jurisdiction, the court ruled that, legally speaking, Texas had remained a United States state ever since it first joined the Union. the court further held that the Constitution did not permit states to unilaterally secede from the United States, and that the ordinances of secession, and all the acts of the legislatures within seceding states intended to give effect to such ordinances, were "absolutely null
Any argument Texas had that they could secede, was already ruled on.