MR. JUSTICE HOLMES delivered the opinion of the Court.
This is a bill in equity alleging that the plaintiffs are qualified electors residing in Houston, Texas, and of the Democratic political faith; that on January 27, 1921, the City Democratic Executive Committee of Houston made and published a rule that negroes would not be allowed to vote in the Democratic City Primary Election to be held on February 9, 1921; that the Committee and Judges of Election threatened to enforce the rule, contrary to the Constitution of the United States; and praying an injunction to restrain the Committee and Judges of Election from carrying out their threats. The bill was filed on February 3, 1921. On February 5, 1921, it was demurred to generally, the demurrer maintaining that the rule did not infringe the Fifteenth Amendment. On February 7, 1921, the demurrer was sustained and the bill was dismissed with costs. The plaintiffs appealed to the Court of Civil Appeals, but that Court held that at the date of its decision, months after the election, the cause of action had ceased to exist and that the appeal would not be entertained on the question of costs alone. It therefore dismissed the appeal with costs. Error is assigned here on the ground that the Fifteenth Amendment prohibits the discrimination which was made the basis of the complaint, and that the decision denied the plaintiffs their constitutional rights.
When as here there is a plain assertion of federal rights in the lower court, local rules as to how far it shall be reviewed on appeal do not necessarily prevail. Davis v. Wechsler, 263 U.S. 22, 24. Whether the right was denied or not given due recognition by the Court of Civil Appeals