Askew v. Hargrave
In Askew v. Hargrave, 401 U.S. 476, 91 S.Ct. 856, 28 L.Ed.2d 196 (1971) the Supreme Court vacated the judgment of the three judge court and held that the district court should have abstained where there was pending in the state courts a claim which if sustained would "obviate the necessity of determining the Fourteenth Amendment question."
The decision was based upon principles of abstention and not 28 U.S.C. Sec. 1341.