The Crawford litigation began in 1963 as a class action on behalf of black high school students seeking to desegregate a high school in Los Angeles. Before trial, the complaint was amended to assert a desegregation claim on behalf of all black and Hispanic students attending school in Los Angeles Unified School District. The case went to trial in 1968 under a stipulation that permitted the court to consider activities of Ds occurring from May 1, 1963, to the time of trial. The trial court rendered its decision on May 12, 1970, finding that the District schools were substantially segregated and concluding that this segregation was both de facto and de jure in origin. The California Supreme Court affirmed on the basis of its previous decision in Jackson that the California Constitution imposed a duty upon school boards to take reasonably feasible steps to alleviate segregation in the public schools, regardless of its cause. The court then remanded the case to the trial court for the development of a reasonably feasible desegregation plan. The trial court rejected the voluntary desegregation plan submitted by D and ordered the implementation of a plan calling for large-scale mandatory pupil reassignment and transportation. The court-ordered plan went into effect in the fall of 1978. In October 1979, the trial court began hearings to determine the constitutional sufficiency of its court-ordered plan. On November 6, 1979, before the hearings could be completed, the voters of California approved Proposition I, an initiative measure which amended the California Constitution to limit the power of state courts to order mandatory pupil reassignment and transportation on the basis of race. In effect, the state courts were forbidden to order those measures except in circumstances where federal courts could do so to remedy violations of the United States Constitution. In addition, Proposition I authorized any court having jurisdiction, upon application by any interested person, to modify existing judgments or decrees containing provisions for mandatory pupil reassignment and transportation, unless such modification would be prohibited by the United States Constitution. D applied to the California courts for an order halting mandatory pupil reassignment and transportation in the District. That application was denied on the ground that the trial court in Crawford I had found de jure segregation and thus the elimination of mandatory pupil reassignment and transportation in the District would be prohibited by the United States Constitution. The California Court of Appeal reversed and vacated. The appellate court determined that the 1970 findings by the trial court in Crawford I did not support its conclusion of de jure segregation when viewed in light of subsequent Supreme Court decisions emphasizing the need for showing specific discriminatory intent. Because only de facto segregation existed in the District schools, it concluded that a federal court would not be authorized under federal law to order pupil assignment and transportation. Consequently, Proposition I barred the state court from doing so. The court thereupon vacated the orders. P filed the present case while Crawford was still pending in the California Superior Court following the remittitur from Crawford II. The district court refused to give res judicata effect to the Crawford litigation because it determined that no final judgment had yet been entered in that case and that retrial of the de jure issue on remand had not been foreclosed by the appellate court's remittitur. A three-judge panel of this court reversed the district court on the ground that the Crawford judgment had since become final and that therefore relitigation of the claim that the District was segregated de jure on or before September 10, 1981, was barred by the doctrines of res judicata and collateral estoppel. P's petition for rehearing en banc was granted.