Green

While litigation concerning the constitutionality of a state statute was pending in state court, four individual plaintiffs filed this federal court challenge to the same statute, alleging similar constitutional defects to those alleged by the state court litigants. The district court dismissed the *1089 case, holding that because the federal court plaintiffs could have intervened in the state court proceedings, they were obligated to do so, and could not proceed in federal court.

This case thus raises questions at the core of the interaction of our dual system of courts, state and federal. Each system is competent to decide federal constitutional issues, and each is entrusted with doing so in appropriate cases. The question whether, in the interests of judicial efficiency and of comity, federal courts should refuse to decide cases within their constitutionally and eongressionally-conferred jurisdiction has been a recurring one. See Quackenbush v. Allstate Ins. Co., 517 U.S. 706 , 116 S.Ct. 1712 , 135 L.Ed.2d 1 (1996); New Orleans Pub. Serv. Inc. v. Council of the City of New Orleans, 491 U.S. 350 , 109 S.Ct. 2506 , 105 L.Ed.2d 298 (1989) (“NOPSI ”); Colo. River Water…