Full opinion text
Affirmed in part and reversed in part by published opinions. A per curiam opinion announced the judgment of the court. Judge TRAXLER delivered the opinion of the court with respect to Parts I, II, IV, and V, in which Chief Judge WILKINSON and Judges WIDENER, WILKINS, NIEMEYER, and WILLIAMS joined, and an opinion with respect to Parts III and VI, in which Judges WILKINS and WILLIAMS joined. Chief Judge WILKINSON wrote an opinion concurring in part in which Judge NIEMEYER joined. Judge WIDENER wrote an opinion concurring in part and dissenting in part. Judge LUTTIG wrote an opinion concurring in the judgment in part and dissenting from the judgment in part. Judges MOTZ and KING wrote a separate opinion in which Judges MICHAEL and GREGORY joined. OPINION PER CURIAM: This case was argued before the en banc Court on February 27, 2001. The parties presented a number of issues for our consideration, including whether the district court erred in (1) finding that unitary status had been achieved and awarding attorneys’ fees to plaintiff-intervenors based on this finding; (2) holding that the establishment of a magnet schools program was an ultra vires, unconstitutional act justifying an award of nominal damages and attorneys’ fees; (3) enjoining the Charlotte-Mecklenburg School Board from considering race in the future assignment of students or allocation of educational resources; and (4) sanctioning the Board for failing to comply with the district court’s discovery order. Having considered the briefs and arguments of the parties, a majority of the Court holds: (1) by a 7-4 vote (Chief Judge Wilkinson and Judges Widener, Wilkins, Niemeyer, Luttig, Williams and Traxler in the affirmative), the school system has achieved unitary status, but by a 6-5 vote (Chief Judge Wilkinson and Judges Niemeyer, Michael, Motz, King and Gregory in the affirmative) attorneys’ fees for work done on the unitary status issue are denied; (2) by a 6-5 vote (Chief Judge Wilkinson and Judges Niemeyer, Michael, Motz, King, and Gregory in the affirmative), the Board did not forfeit its immunity for the establishment of the magnet schools program, and nominal damages and attorneys’ fees in that regard are denied; (3) by a unanimous vote, the injunction is vacated; and (4) by a unanimous vote, the imposition of sanctions is affirmed. The judgment of the district court is therefore affirmed on the finding of unitary status and the imposition of sanctions, reversed as to the finding of liability for nominal damages for the establishment of the magnet schools program, reversed as to the imposition of attorneys’ fees for any reason, and reversed on the issuance of the injunction. Unitary status having been achieved, the judgment of the district court vacating and dissolving all prior injunctive orders and decrees is affirmed. The Board is to operate the school system without the strictures of these decrees no later than the 2002-2003 school year. AFFIRMED IN PART AND REVERSED IN PART. TRAXLER, Circuit Judge: This case is hopefully the final chapter in the saga of federal court control over the Charlotte-Mecklenburg Schools (“CMS”). Since 1971 CMS has operated under a federally supervised desegregation plan that included limited use of racial ratios, pairing and grouping of school zones, and extensive busing. So successful was the plan that the district court removed the case from the active docket in 1975, expressing its belief that the once reluctant school board was committed to achieving desegregation and was already well on the way toward a unitary school system. Since then, two generations of students have passed through CMS and, until the present case, not one person has returned to court alleging that segregative practices have been continued or revived. Now, nearly three decades later and prompted by a lawsuit filed by a white student challenging the magnet schools admissions policy, the question of whether CMS has achieved unitary status has been placed before our courts. In 1999, the district court, after a lengthy hearing and searching inquiry, concluded that CMS had indeed achieved unitary status by eliminating the vestiges of past discrimination to the extent practicable. This conclusion was not reached in haste; it was the result of a two-month hearing and an examination of extensive testimony and evidence relating to every aspect of CMS’s educational system. A majority of this court now affirms the district court’s holding on this issue, satisfied that CMS has dismantled the dual school system. In sharp contrast to the situation in the late 1960s, when black students were segregated in black schools and taught by a predominantly black staff, CMS students today are educated in an integrated environment by an integrated faculty. Nor do we turn over control to an indecisive and uncommitted school board. CMS currently operates under the firm guidance of an integrated school board which has clearly demonstrated its commitment to a desegregated school system. In sum, the “end purpose” of federal intervention to remedy segregation has been served, and it is time to complete the task with which we were charged — to show confidence in those who have achieved this success and to restore to state and local authorities the control of their school system. Consequently, a majority of this court affirms the district court’s unitary status determination. However, while a majority of my colleagues agree that CMS has achieved unitary status, and have graciously joined me on this point, I respectfully depart from a separate majority’s decision to reverse the district court’s holding that CMS’s magnet schools program, which was implemented in 1992, was an ultra vires, unconstitutional act justifying an award of nominal damages and attorney fees. By denying children, on account of their race, an equal opportunity to compete for open, unclaimed slots in CMS’s extraordinary magnet program, I believe the school board pushed too far and did more than either was required or permitted. Just as the educational process of the 1960s unconstitutionally deprived black children of educational opportunities solely on account of their race, the magnet schools admissions policy deprives white children of educational opportunities solely on account of their race. Consequently, I depart from the separate majority in that I would affirm the district court’s conclusion that the magnet schools program violated the Equal Protection Clause of the Fourteenth Amendment and the liability of the school board for the violation. I. In 1896, the Supreme Court upheld a Louisiana statute “providing for separate railway carriages for the white and colored races.” Plessy v. Ferguson, 163 U.S. 537, 540, 16 S.Ct. 1138, 41 L.Ed. 256 (1896). The Plessy majority characterized the statute as “not necessarily implying] the inferiority of either race,” id. at 544, 16 S.Ct. 1138, but the first Justice Harlan, in dissent, aptly described the true aim of the law: “Everyone knows that the statute in question had its origin in the purpose, not so much to exclude white persons from railroad cars occupied by blacks, as to exclude colored people from coaches occupied by or assigned to white persons,” id. at 557, 16 S.Ct. 1138 (Harlan, J., dissenting). Justice Harlan further “den[ied] that any legislative body or judicial tribunal may have regard to the race of citizens when the civil rights of those citizens are involved.” Id. at 554-55, 16 S.Ct. 1138 (Harlan, J., dissenting). Unfortunately, the principle of “separate but equal” reached much farther than Louisiana railways, and was applied to other public services, including education. The march of progress eventually proved the correctness of Justice Harlan’s principled stand. Segregation, in all of its manifestations, was “arbitrary” and “wholly inconsistent with the civil freedom and the equality before the law established by the Constitution.” Id. at 561-62, 16 S.Ct. 1138 (Harlan, J., dissenting). Early efforts aimed at combating the injustice wrought by Plessy in educational settings often centered on state-funded graduate and professional schools. See, e.g., Missouri ex rel. Gaines v. Canada, 305 U.S. 337, 59 S.Ct. 232, 83 L.Ed. 208 (1938); see generally Mark V. Tushnet, The NAACP’s Legal Strategy Against Segregated Education 1925-1950 (1987). In Gaines, an African-American student was denied admission to the University of Missouri School of Law on account of his race. Missouri had no “separate but equal” law school for its African-American citizens and instead offered to pay Gaines’ tuition and expenses for a legal education in another state. The Supreme Court held that Missouri’s offer denied Gaines equal protection of the laws. The Court observed that “[t]he admissibility of laws separating the races in the enjoyment of privileges afforded by the State rests wholly upon the equality of the privileges which the laws give to the separated groups within the State.” Gaines, 305 U.S. at 349, 59 S.Ct. 232. Though providing only small victories, cases like Gaines exposed “separate but equal” for the untenable proposition that it was. In 1954, the Supreme Court recognized the futility of measuring equality in segregated facilities. See Brown v. Board of Educ., 347 U.S. 483, 74 S.Ct. 686, 98 L.Ed. 873 (1954) (Brown I). Presented with a direct attack on Plessy in a secondary education case, the Court held that “segregation of children in public'schools solely on the basis of race” violated the Equal Protection Clause of the Fourteenth Amendment. Id. at 493, 74 S.Ct. 686. The Court emphasized that an educational “opportunity, where a state has undertaken to provide it, is a right which must be made available to all on equal terms.” Id. Recognizing that segregation differed from locality to locality, the Supreme Court subsequently declined to craft a broad, one-size-fits-all remedy, and instead instructed the federal district courts to oversee the implementation of appropriate relief based on the dictates of local circumstances. See Brown v. Board of Educ., 349 U.S. 294, 299, 75 S.Ct. 753, 99 L.Ed. 1083 (1955) (Brown II) (“Because of their proximity to local conditions and the possible need for further hearings, the courts which originally heard these cases can best perform th[e] judicial appraisal.”). The district courts were directed to make use of the “traditional attributes of equity power,” id. at 300, 75 S.Ct. 753, to ensure that students were “admit[ted] to public schools on a racially nondiscriminatory basis,” id. at 301, 75 S.Ct. 753. However, under the Brown opinions it was unclear whether a school district was required to take affirmative steps to remedy the constitutional violation, see, e.g., Briggs v. Elliott, 132 F.Supp. 776, 777 (E.D.S.C.1955) (holding that Brown merely prohibited school districts from using, the force of law to separate the races), and very little progress resulted. Before the Supreme Court provided further guidance to the lower federal courts, in 1965 the Swann plaintiffs, who were the original class action plaintiffs representing the interests of African-American children in the district, challenged as constitutionally inadequate the efforts of CMS in complying with Brown. The school district’s desegregation plan was based on freedom of choice whereby “any child, without regard to race, and without regard to minority or majority of race in any particular school, might freely transfer to another school of his ’choice.” Swann v. Charlotte-Mecklenburg Bd. of Educ., 243 F.Supp. 667, 668 (W.D.N.C.1965). The district court approved the plan, observing that more could be done “to increase mixing of the races,” but that the law imposed “no such duty upon ... the School Board.” Id. at 670. Concerned at the slow pace of school desegregation throughout the nation, the Supreme Court held in 1968 that school boards had an “affirmative duty” to end the state-imposed dual system of education. Green v. County Sch. Bd., 391 U.S. 430, 437, 88 S.Ct. 1689, 20 L.Ed.2d 716 (1968). The Justices underscored that “in desegregating a dual system a plan utilizing ‘freedom of choice’ is not an end in itself.” Id. at 440, 88 S.Ct. 1689. The Swann plaintiffs then filed in the district court a motion for further relief “seeking] greater speed in desegregation of the Charlotte-Mecklenburg schools, and requesting] elimination of certain other alleged racial inequalities.” Swann v. Charlotte-Mecklenburg Bd. of Educ., 300 F.Supp. 1358, 1360 (W.D.N.C.1969). The district court, guided by the mandate of Green, see Swann, 300 F.Supp. at 1362, made a number of factual findings and concluded that the school district remained highly segregated. The district court noted that over half of CMS’s 24,000 African-American students “attend schools that are all black, or very nearly all black, and most of the 24,000 have no white teachers.” Id. at 1360. However, the court found no violations “in the use of federal funds; the use of mobile classrooms; quality of school buildings and facilities; athletics; PTA activities; school fees; free lunches; books; elective courses; nor in individual evaluation of students.” Id. at 1372. The district court directed CMS to submit “a positive plan for faculty desegregation effective in the fall of 1969, and a plan for effective desegregation of pupil population, to be predominantly effective in the fall of 1969 and to be completed by the fall of 1970.” Id. at 1360. The board procrastinated, but eventually submitted an enervated desegregation plan that the district court approved “with great reluctance” on a temporary basis. Swann v. Charlotte-Mecklenburg Bd. of Educ., 306 F.Supp. 1291, 1298 (W.D.N.C.1969). CMS officials, however, continued to drag their feet, and the district court was forced to appoint its own expert, Dr. John A. Finger, to craft an efficacious desegregation plan. See Swann v. Charlotte-Mecklenburg Bd. of Educ., 311 F.Supp. 265 (W.D.N.C.1970). Dr. Finger’s plan, adopted by the district court, included limited use of mathematical ratios, pairing and grouping of school zones, and busing. See id. We affirmed a portion of the plan, but vacated provisions dealing with the busing of elementary school students because of the perceived burdens on small children and the cost of purchasing new buses. See Swann v. Charlotte-Mecklenburg Bd. of Educ., 431 F.2d 138, 147 (4th. Cir.1970) (en banc). We remanded “for reconsideration of the assignment of pupils in the elementary schools.” Id. The Supreme Court granted certiorari and reinstated the district court’s plan pending further proceedings. See Swann v. Charlotte-Mecklenburg Bd. of Educ., 399 U.S. 926, 90 S.Ct. 2247, 26 L.Ed.2d 791 (1970). The district court conducted eight days of hearings and examined five different desegregation plans. The district court concluded the Finger plan to be the best of the five, encompassing “a reasonable ... collection of methods for solving the problem” of the dual system. Swann v. Char lotte-Mecklenburg Bd. of Educ., 318 F.Supp. 786, 800 (W.D.N.C.1970). As for busing and the cost of new buses, the district court found that the Finger plan took “proper advantage of traffic movement” and that new buses would cost only $660,000, a far cry from the millions of dollars that CMS had originally estimated. See id. at 797-98. Two months later, the Supreme Court granted certiorari and undertook an in-depth review of the power of the federal district courts to craft such sweeping desegregation remedies. See Swann v. Charlotte-Mecklenburg Bd. of Educ., 402 U.S. 1, 91 S.Ct. 1267, 28 L.Ed.2d 554 (1971). The Supreme Court affirmed the desegregation plan adopted by the district court, and in the course of its opinion identified and offered guidance in “four problem areas.” Id. at 22, 91 S.Ct. 1267. First, the Court addressed the issue of the district court’s use of racial ratios. While the Supreme Court approved of a limited use of mathematical ratios in a plan crafted by a district court, it emphasized that such ratios were “a starting point ... rather than an inflexible requirement.” Id. at 25, 91 S.Ct. 1267. The Court reminded district courts that “[t]he constitutional command to desegregate schools does not mean that every school in every community must always reflect the racial composition of the school system as a whole.” Id. at 24, 91 S.Ct. 1267. Second, the Court dealt with single-race schools. Though the Court concluded that schools consisting of predominantly one race were not per se unconstitutional, the Court instructed the district courts to utilize “close scrutiny to determine that school assignments are not part of state-enforced segregation.” Id. at 26, 91 S.Ct. 1267. Third, the Court considered alterations of attendance zones. The Court held “that the pairing and grouping of noncontiguous school zones is a permissible tool,” id. at 28, 91 S.Ct. 1267, but declined to craft “rigid rules” in light of differing local circumstances, id. at 29, 91 S.Ct. 1267. Finally, the Court tackled the busing issue. The Court confirmed that a district court could order “bus transportation as one tool of school desegregation,” but within reasonable time and distance restrictions. Id. at 30, 91 S.Ct. 1267. Shortly after the Supreme Court issued its landmark Swann opinion, CMS asked the district court to abandon the Finger plan and permit the substitution of a “feeder plan” whereby schools would draw pupils from designated attendance areas in an effort to keep children together for their entire public school career. See Swann v. Charlotte-Mecklenburg Bd. of Educ., 328 F.Supp. 1346 (W.D.N.C.1971). Citing concerns of resegregation and the placement of additional burdens on African-American children, the district court questioned the feeder plan. See id. at 1350-53. CMS then withdrew its original feeder plan and began work on a modified version. See id. at 1353. The district court eventually approved a revised feeder plan that reopened several former black schools and prevented over- and under-utilization of facilities. See Swann v. Charlotte-Mecklenburg Bd. of Educ., 334 F.Supp. 623 (W.D.N.C.1971). However, within just two years it became clear that CMS’s revised feeder plan was inadequate “for dealing with foreseeable problems” in the dismantling of the dual system. Swann v. Charlotte-Mecklenburg Bd. of Educ., 362 F.Supp. 1228, 1229 (W.D.N.C.1973). The district court found “that various formerly black schools and other schools will turn black under the feeder plan,” id., and that “[rjacial discrimination through official action has not ended in this school system,” id. at 1230. The district court again instructed CMS to design a new pupil assignment plan “on the premise that equal protection of laws is here to stay.” Id. at 1238. In 1974 CMS adopted and the district court approved new guidelines and policies for pupil assignment. See Swann v. Charlotte-Mecklenburg Bd. of Educ., 379 F.Supp. 1102 (W.D.N.C.1974). The plan was designed by a citizens advisory group working with the board in an effort to reach “an acceptable consensus” on school desegregation in CMS. Id. at 1103. The plan’s most promising features were the avoidance of any majority black schools (with the exception of Hidden Valley, an exempted school), and a more equal distribution of the busing burden. See id. at 1105-1110. Praising the board for making “a clean break with the essentially ‘reluctant’ attitude which dominated Board actions for many years,” the district court predicted that the policies and positive attitude would eventually result in a unitary school system. Id. at 1103. The district court closed Swann in 1975 and removed the case from the active docket. See Swann v. Charlotte-Mecklenburg Bd. of Educ., 67 F.R.D. 648 (W.D.N.C.1975). In so doing, the district court observed that the board was “actively and intelligently addressing” recurrent problems related to dismantlement of the dual system. Id. at 649. The district court was so satisfied with the progress being made that it questioned whether it would ever be confronted with a motion to reopen the litigation. See id. For three years there was no action in the case. This changed in 1978 when a group of white parents sought to enjoin CMS from reassigning over 4000 students in an effort to maintain racial balance in certain schools. See Martin v. Charlotte-Mecklenburg Bd. of Educ., 475 F.Supp. 1318 (W.D.N.C.1979). The parents attacking the 1978 student assignment plan “offered no live evidence but offered and relied upon a few written exhibits and admissions from the pleadings.” Id. at 1321. Not surprisingly, the district court rejected the parents’ challenge to the student assignment plan and praised CMS for its zeal in dismantling the dual system. In 1980, CMS and the Swann plaintiffs again returned to the district court. The parties informed the district court that the African-American student population in CMS’s elementary schools had grown from twenty-nine percent to forty percent, making it difficult to avoid predominantly black student bodies. To provide the board with some flexibility, the district court permitted operation of elementary schools with African-American student bodies of plus fifteen percent above the district-wide average. See Swann v. Charlotte-Mecklenburg Bd. of Educ., No.1974 (W.D.N.C. Apr. 17, 1980). Since 1980, neither the board nor the Swann plaintiffs have approached the district court regarding alteration of the earlier desegregation orders. And, until the present litigation, the Swann plaintiffs have never attempted to reopen the case in order to address any alleged failure by the board to comply with the district court’s desegregation orders. The controversy before us today arose in September 1997 when William Capacchione (“Capacchione”) filed suit against CMS on behalf of his daughter, Cristina, alleging that she had been unconstitutionally denied admission to a magnet school program on account of her race. In 1992, without prior court approval, CMS had adopted a desegregation plan focused mainly on the use of magnet schools. In filling magnet schools, CMS had instituted a black and a non-black lottery to achieve racial balance. If a sufficient number of blacks or whites did not apply and fill the seats allotted to their respective races, then CMS would actively recruit children of the desired race despite lengthy waiting lists made up of children of the other race. If the recruitment drive faded, CMS usually left the available slots vacant. Cristina, who is white, was placed on a waiting list and eventually denied admission to a program at the Olde Providence magnet school, which CMS marketed as “a school to benefit everyone.” J.A. XXXII-15,670. The original Swann plaintiffs moved to reactivate Sivann and to consolidate it with Capacchione’s suit. They asserted that the vestiges of the dual school system had not been abolished and that the use of race in the magnet admissions policy was necessary for the school district to comply with the prior desegregation orders. The district court granted the motion and later permitted Capacchione to intervene in the Swann litigation. Seeking a finding that CMS had eradicated the vestiges of past discrimination, another group of parents, led by Michael P. Grant (“Grant”), was also permitted to intervene in the litigation. After a two-month bench trial, the district court determined that CMS had achieved unitary status, that the race-based admissions policy for CMS’s magnet schools fell outside prior orders and was not narrowly tailored to achieve a compelling state interest, and that an injunction was warranted. The district court “en-joinfed] CMS from any further use of race-based lotteries, preferences, and set-asides in student assignment.” Capacchione v. Charlotte-Mecklenburg Schs., 57 F.Supp.2d 228, 292 (W.D.N.C.1999). Citing interests in stability, the district court concluded that the injunction would not affect student assignments for the 1999 2000 school year, but would apply to student assignments for the 2000-2001 school year. See id. at 292 n. 52. The district court awarded Capacchione nominal damages in recognition of the constitutional violation and also awarded the plaintiff-intervenors attorney fees. CMS and the Swann plaintiffs filed notices of appeal, and CMS moved to stay the injunction, except as applied to the magnet schools, until the 2001-02 school year. The Swann plaintiffs moved for a complete stay pending appeal. On November 15, 1999, the district court denied the motions. CMS and the Swann plaintiffs, pursuant to Federal Rule of Appellate Procedure 8(a)(2), moved this court for a stay. On December 30, 1999, we stayed the district court’s injunction pending further order of this court. After briefing and appellate arguments, a divided panel of this court vacated and remanded the district court’s unitary status determination, holding that the district court’s findings were insufficient in the areas of student assignment, facilities and resources, transportation, and student achievement. As for CMS’s magnet schools admissions policy, the panel held that the policy was specifically permitted by prior court orders and that the policy did not violate the Constitution. The panel also vacated the district court’s injunction, the award of nominal damages, and the award of attorney fees. See Belk v. Charlotte-Mecklenburg Bd. of Educ., 233 F.3d 232 (4th Cir.2000). A majority of the active circuit judges thereafter voted to hear this appeal en banc. II. Unitary Status The district court’s unitary status finding is reviewed for clear error. See Riddick v. School Bd., 784 F.2d 521, 533 (4th Cir.1986); Fed.R.Civ.P. 52(a). “A finding is clearly erroneous when, although there is evidence to support it, on the entire evidence the reviewing court is left with the definite and firm conviction that a mistake has been committed.” Faulconer v. Commissioner, 748 F.2d 890, 895 (4th Cir.1984). In clarifying the clearly erroneous standard, the Supreme Court has explained: If the district court’s account of the evidence is plausible in light of the record viewed in its entirety, the court of appeals may not reverse it even though convinced that had it been sitting as the trier of fact, it would have weighed the evidence differently. Where there are two permissible views of the evidence, the factfinder’s choice between them cannot be clearly erroneous. Anderson v. City of Bessemer City, 470 U.S. 564, 573-74, 105 S.Ct. 1504, 84 L.Ed.2d 518 (1985). The Supreme Court also stressed that even when appellate review is based primarily on documentary evidence, the clearly erroneous standard of review remains the same. See id. at 574, 105 S.Ct. 1504. So long as the district court’s unitary status determination rests on a permissible view of the evidence, it must be affirmed. The Supreme Court has declined to define or provide a “fixed meaning” for the term “unitary.” Freeman v. Pitts, 503 U.S. 467, 487, 112 S.Ct. 1430, 118 L.Ed.2d 108 (1992). However, in light of the aim of Brown I, which was “the elimination of state-mandated or deliberately maintained dual school systems,” Milliken v. Bradley, 418 U.S. 717, 737, 94 S.Ct. 3112, 41 L.Ed.2d 1069 (1974) (Milliken I), a school system must be declared unitary when it no longer discriminates between children on the basis of race, see Green, 391 U.S. at 442, 88 S.Ct. 1689. The burden of proof falls on the party seeking an end to court supervision. See Freeman, 503 U.S. at 494, 112 S.Ct. 1430. In undertaking a unitary status inquiry, a court must ask “whether the Board ha[s] complied in good faith with the desegregation decree since it was entered, and whether the vestiges of past discrimination ha[ve] been eliminated to the extent practicable.” Board of Educ. v. Dowell, 498 U.S. 237, 249-50, 111 S.Ct. 630, 112 L.Ed.2d 715 (1991). Implicit in the Supreme Court’s use of the term “practicable” is “a reasonable limit on the duration of ... federal supervision.” Coalition to Save Our Children v. State Bd. of Educ., 90 F.3d 752, 760 (3d Cir.1996); see also Dowell, 498 U.S. at 247, 111 S.Ct. 630 (“From the very first, federal supervision of local school systems was intended as a temporary measure to remedy past discrimination.”). Hence, the goals of a desegregation order not only encompass a remedy for the violation, but also prompt restoration of local control. See Freeman, 503 U.S. at 490, 112 S.Ct. 1430 (“Returning schools to the control of local authorities at the earliest practicable date is essential to restore their true accountability in our governmental system.... Where control lies, so too does responsibility.”); Milliken I, 418 U.S. at 741-42, 94 S.Ct. 3112 (“No single tradition in public education is more deeply rooted than local control over the operation of schools; local autonomy has long been thought essential both to the maintenance of community concern and support for public schools and to quality of the educational process.”). Among the most important reference points in determining whether a school board has fulfilled its duties so that local control may be resumed are the factors set out in Green: student assignment, faculty assignment, facilities and resources, transportation, staff assignment, and extracurricular activities. See Green, 391 U.S. at 435, 88 S.Ct. 1689. In its discretion, a court conducting a unitary status hearing may consider other relevant factors not mentioned in Green. See Freeman, 503 U.S. at 492, 112 S.Ct. 1430. We address the district court’s consideration of each factor in turn, but only to determine whether “the district court’s account of the evidence is plausible in light of the record viewed in its entirety.” Anderson, 470 U.S. at 573-74, 105 S.Ct. 1504. A. Student Assignment Student assignment is perhaps the most critical Green factor because state-mandated separation of pupils on the basis of race is the essence of the dual system. See Freeman, 503 U.S. at 474, 112 S.Ct. 1430 (observing that the issue of student assignment is “fundamental” because “under the former de jure regimes racial exclusion was both the means and the end of a policy motivated by disparagement of ... the disfavored race”). To determine whether a school was racially balanced or imbalanced, the district court adopted a plus/minus fifteen percent variance from the district-wide ratio of black to white students. See Capacehione, 57 F.Supp.2d at 246. However, the district court emphasized “that there is no level of compliance with the standard that is determinative.” Id. When schools are outside the variance, a “reasonable and supportable explanation! ]” will suffice. Id. The district court did not err in adopting a plus/minus fifteen percent variance. Considering that the only variance ever approved by the district court in the course of the Swann litigation was a “ ‘plus 15%’ from the district-wide average,” id. at 245, the addition of a minus fifteen percent is reasonable. Moreover, the Supreme Court has permitted a “limited use ... of mathematical ratios” by district courts, Swann, 402 U.S. at 25, 91 S.Ct. 1267, and much higher variances have been used to define desegregation, see Manning v. Hillsborough County Sch. Bd., 244 F.3d 927, 935 (11th Cir.2001) (using a plus/minus twenty percent variance); see generally, David J. Armor, Forced Justice: School Desegregation and the Law 160 (1995) (observing that in over seventy percent of the school districts with desegregation plans where racial balance is measured by numerical standards, a variance of plus/minus fifteen percent or greater is used). In sum, the plus/minus fifteen percent variance is clearly within accepted standards, and provides a reasonable starting point in the unitary status determination. 1. CMS’s Compliance Record The district court began by observing that since 1970, of the 126 schools in operation, “only twenty schools (16%) have had black student bodies higher than 15% above the district-wide ratio for more than three years, and only seventeen schools (13%) have had black student bodies lower than 15% below the district-wide ratio for more than three years.” Capacchione, 57 F.Supp.2d at 248 (footnote omitted). In addition, the district court found that CMS has not operated a single-race school since 1970. See id. The district court also turned to two desegregation indices: the dissimilarity index and the index of interracial exposure. The former “measures the degree of racial imbalance, and it is derived by comparing the racial composition of each school to the district-wide composition,” J.A. XXXIII-16,172, and the latter measures “the average percent white in schools attended by black students, weighted by the proportion of black students in each school.” J.A. XXXIII-16,172. According to the report of the plaintiff-intervenors’ expert witness, Dr. David J. Armor, a dissimilarity value of twenty or below signifies “a highly balanced school system” and a score under thirty signifies “a substantially desegregated system.” J.A. XXXIII-16,172. CMS’s dissimilarity score was sixteen in 1980 and twenty-six in 1995. From this it is clear that CMS quickly desegregated in the 1970s and continues to maintain a “substantially desegregated system.” The dissimilarity index also indicates that CMS has better racial balance than several comparable districts did when they were declared unitary. See J.A. XXXIII-16,173. The index of interracial exposure, like the dissimilarity index, shows that CMS has made great leaps of progress. A score of zero on the exposure index signifies total segregation, while a score of fifty or above indicates a “highly desegregated system.” J.A. XXXIII-16,172. Schools in CMS typically score above fifty, whereas before the desegregation order the schools’ scores hovered near twenty or below. See J.A. XXXIII-16,194-96. CMS and the Swann plaintiffs correctly point out that the data suggest that in recent years racial imbalance has increased in some schools. Aware of this trend, the district court made a number of findings on growth and demographic change in the Charlotte-Mecklenburg area. The most revealing findings are as follows: • the county population has increased from 354,656 in 1970 to 613,310 in 1997 • in 1970 the school district was the forty-third largest in the nation and is today the twenty-third largest • among cities with more than 500,000 people, Charlotte ranks second in population growth in the 1990s • the racial composition of the county has changed from seventy-six percent white and twenty-four percent black in 1970 to sixty-eight percent white, twenty-seven percent black, and five percent other in 1997 • the current racial composition of schoolchildren is fifty percent white, forty-two percent black, and eight percent other • as the county has become more suburban the inner city and nearby suburbs have lost large numbers of white residents as they spread farther out into the formerly rural sections of the county • some middle suburban communities that were once all white are now predominately black • the rural black population in the southern part of the county has remained relatively constant while the white population has tripled because of suburbanization See Capacchione, 57 F.Supp.2d at 236-39. “These findings are supported by the report of the plaintiff-intervenors’ expert in demographics, Dr. William Clark. See J.A. XXXIII-16230-306. Accordingly, the district court concluded that “[t]here can be no doubt that demography and geography have played the largest role in causing imbalance.” Capacchione, 57 F.Supp.2d at 250. Testimony from Dr. John Murphy, CMS’s superintendent from 1991 to 1995, corroborates the district court’s conclusion. Dr. Murphy testified that when he assumed his duties he “was quite concerned about the increasing difficulty in bringing about racial balance ... because of the demographic shifts that were occurring.” J.A. VI-2712. Population growth translated into more automobiles on the road, making increased busing impracticable because “the travel time to move youngsters from the suburbs into the city with the flow of rush hour traffic was a problem.” J.A. VI-2732. In the fall of 1991, CMS hired Dr. Michael J. Stolee to examine the problem and offer solutions. Dr. Stolee also concluded that CMS’s task “has been complicated by population growth,” J.A. XXXII-15,571, and he recommended the adoption of a magnet schools program, which CMS promptly implemented. The Supreme Court has dealt with similar population growth and shifting demographics in the context of unitary status. In Freeman, the court unequivocally stated that “racial imbalance ... [is] not tantamount to a showing that the school district [is] in noncompliance with the decree or with its duties under the law.” 503 U.S. at 494, 112 S.Ct. 1430. Brown I, of course, does not mandate that racial balance be pursued in perpetuity. Once the original racial imbalance caused by a constitutional violation has been rectified, “the school district is under no duty to remedy imbalance that is caused by demographic fae-tors.” Freeman, 503 U.S. at 494, 112 S.Ct. 1430. The Swann plaintiffs contend that consideration of demographics and the rationale of Freeman are misplaced because the growth and shifting demographics of DeKalb County, Georgia, the school district under court order in Freeman, exceeded that of Charlotte-Mecklenburg. While CMS’s growth rates and demographic shifts certainly do not equal those experienced in DeKalb, we can find nothing in Freeman limiting its holding to the specific facts of DeKalb County or establishing DeKalb as the standard for measuring imbalance caused by demographic factors. On the contrary, the opinion speaks in general terms. The Supreme Court observed that in the United States “it is inevitable that the demographic makeup of school districts, based as they are on political subdivisions such as counties and municipalities, may undergo rapid change.” Id. at 495, 112 S.Ct. 1430. Mobility, the Court noted, “is a distinct characteristic of our society.” Id. at 494, 112 S.Ct. 1430. Similarly, the Swann plaintiffs contend that unlike DeKalb County, Mecklenburg County has become more integrated as the black population has increased. This is simply not true. For example, a report prepared in 1992 by the Charlotte-Mecklenburg Planning Staff for Chairman Arthur Griffin concluded that “Charlotte-Mecklenburg continues to be a city of segregated neighborhoods” with “Concentrations of Black households ... generally located in the central city.” J.A. XXI-10,485; see also J.A. XXVIII-13,803 (1992 student assignment plan stating that “housing across the county is not racially integrated. Approximately 50% of all black students live within one district, while only 10% of white students reside in that district.”); J-A. XXII-10,575 (CMS report chronicling growth of the black population and decline of the white population in the inner city). Clearly, increased housing integration is not necessarily a corollary of African-American population growth. Hence, despite the Swann plaintiffs’ best efforts, Freeman cannot be distinguished into nothingness, nor does the standard of review permit this court to reweigh the evidence of the changes in CMS. We also note that when confronted with growing imbalance in certain schools, the district court demanded cogent and supportable explanations from the plaintiff-intervenors, paying special attention to the former de jure schools still in use. See Capacchione, 57 F.Supp.2d at 246. Evidence presented at trial indicated that “[o]f the 16 former black schools that are still open, 13 are currently balanced and have been desegregated for periods ranging from 22 to 28 years. Of the 3 that currently exceed the 4-15% black variance, each has been balanced for at least 22 years.” J.A. XXXIII-16,176. Interestingly, of the seventy-two former white schools that are still open, fifteen are now majority black and were in balance for periods of twelve to twenty-five years. See J.A. XXXIII-16,176. In addition, Dr. Armor examined the seventeen schools in CMS that exceeded the plus fifteen percent variance for three or more years during the last decade. See J.A. XXXIII-16,174 76. Sixteen of the seventeen were balanced for periods ranging from nineteen to twenty-six years, with one school experiencing balance for sixteen years. To the extent that CMS’s pupil reassignments could be assessed, Dr. Armor concluded that changes instituted by CMS were “attempts to maintain or restore racial balance in the face of overwhelming demographic growth and mobility.” J.A. XXXIII-16,176. Indeed, Dr. Armor concluded that imbalance had been reduced in several of the schools because CMS’s magnet program attracted white students from the outer reaches of the county. Long periods of almost perfect compliance with the court’s racial balance guidelines, coupled with some imbalance in the wake of massive demographic shifts, strongly supports the district court’s finding that the present levels of imbalance are in no way connected with the de jure segregation once practiced in CMS. See Freeman, 503 U.S. at 495, 112 S.Ct. 1430 (“Where resegregation is a product not of state action but of private choices, it does not have constitutional implications.”); Manning, 244 F.3d at 944 (“Where a [party seeking a finding of unitary status] shows that demographic shifts are a substantial cause of the racial imbalances, [the party] has overcome the presumption of de jure segregation.”); United States v. Meriwether County, 171 F.3d 1333, 1339 (11th Cir.1999) (observing that a “school district need not wage a battle against demographics to achieve perfect racial balance”). The evidence presented at trial adequately explained why a few schools have become imbalanced, and we can discern no evidence or omissions that indicate clear error has been committed in this regard. 2. Martin and Unitary Status The Swann plaintiffs also point to school sitings, transportation burdens, and school transfers as evidence that the growing imbalance is caused by state action rather than private choices, and that CMS has not complied with the district court’s orders in good faith. In advancing their argument, the Swann plaintiffs rely chiefly on Martin v. Charlotte-Mecklenburg Board of Education, 475 F.Supp. 1318 (W.D.N.C.1979), in which a group of parents sought to enjoin CMS from reassigning over 4000 students in order to maintain racial balance in certain schools. The plaintiffs in Martin based their position on Pasadena City Board of Education v. Spangler, 427 U.S. 424, 96 S.Ct. 2697, 49 L.Ed.2d 599 (1976), and Regents of the University of California v. Bakke, 438 U.S. 265, 98 S.Ct. 2733, 57 L.Ed.2d 750 (1978). In the former case, the Supreme Court reaffirmed that district courts could not order a school district “to rearrange its attendance zones each year so as to ensure that the racial mix desired by the court was maintained in perpetuity,” Spangler, 427 U.S. at 436, 96 S.Ct. 2697, and in the latter the Court struck down a medical school admissions policy that reserved sixteen of one hundred seats in the entering class for applicants who were “ ‘economically and/or educationally disadvantaged’ ” and who were members of certain minority groups, Bakke, 438 U.S. at 274, 98 S.Ct. 2733. The district court in Martin distinguished Spangler by observing that it was but a restatement of the Swann Court’s admonition about the use of racial quotas and that, unlike Pasadena City, CMS had not achieved racially neutral attendance patterns. See Martin, 475 F.Supp. at 1340. As for the Bakke decision, the district court pointed out that no student in CMS was denied “an equal educational opportunity” and that the admissions policy in Bakke was implemented “against a backdrop devoid of specific judicial findings or administrative acknowledgments of the prior segregated status of the school system.” Id. at 1345. Accordingly, the Martin court concluded that CMS’s reassignment of students was “within constitutional limits and should be upheld.” Id. at 1321. The district court took pains to ensure that its opinion would not be interpreted too broadly: “This order simply upholds the actions of the 1978 Board against the attacks by the plaintiffs.” Id. at 1347. In the course of the Martin opinion, the district court observed that CMS had fallen short in four areas: construction and location of facilities in parts of the county likely to enhance desegregation, placement of elementary and kindergarten grades in schools throughout the county, monitoring of student transfers so as to prevent re-segregation, and allocation of the burdens of busing. See id. at 1328-29. However, the district court also noted that CMS had made great progress and that a return to the old system of segregation “has not tempted the present School Board, who are standing fast in their endeavor to run the schools according to law while providing quality education.” Id. at 1347. In Capacchione, the district court correctly observed that “Martin was not a unitary status hearing,” Capacchione, 57 F.Supp.2d at 250, and that because “the desegregation plan was still in its fledgling stages, the Court was inclined to keep the pressure on CMS,” id. at 251. The Capacchione court further observed that post-Martin changes in Charlotte-Mecklenburg counseled looking at the “concerns [of Martin ] in a new light.” Id. The district court’s interpretation of Martin is reasonable and in accord with the rule in this circuit that a district court, as a continuous institution, is “best able to interpret its own orders.” Vaughns v. Board of Educ., 758 F.2d 983, 989 (4th Cir.1985) (school desegregation case). Moreover, the Martin order was issued thirteen years before the Supreme Court made clear in Freeman that the affirmative measures mandated by Green are not meant to remedy “private choices” that lead to resegregation. Freeman, 503 U.S. at 495, 112 S.Ct. 1430. The state of the law and the understanding of duties upon school districts were far different when Martin was handed down. Hence, a number of assertions in Martin cannot be squared with the present state of the law. See, e.g., Martin 475 F.Supp. at 1346 (stating that segregated housing patterns must necessarily lead to the unconstitutional segregation of schools). Ignoring the changes in Charlotte-Mecklenburg and in the law by erecting Martin as the framework for unitary status, as the Swann plaintiffs urged below, would defy common sense and run afoul of developments in the Supreme Court’s school desegregation jurisprudence. See United States Gypsum Co. v. Schiavo Bros., 668 F.2d 172, 176 (3d Cir.1981) (concluding that a successor judge “is empowered to reconsider [the legal conclusions of an unavailable predecessor] to the same extent that his or her predecessor could have”); see also Meriwether County, 171 F.3d at 1339 (“The law does not make a school district a prisoner based on factors, such as demographic tendencies, that are beyond its control.”). We will examine the district court’s Martin findings in turn. a. School Siting The district court found that CMS had not shirked its duties under the law with regard to school sitings. See Capacchione, 57 F.Supp.2d at 251-53. The record reveals that CMS has, to the extent practicable, continually endeavored to site schools in order to foster integration, and has adopted a policy of building schools in areas equally accessible to blacks and whites. Testimony of current board members indicated that in efforts to fulfill this policy, CMS has purchased property in low growth areas for school construction even though schools in predominantly white high growth areas were overcrowded. See J.A. V-1986-87. In 1992 CMS reaffirmed its siting policy and resolved that, “whenever possible,” new schools would be built in areas that would “provide black student enrollment of not less than 10 percent from the census tracts serving the new school.” J.A. XXXII-15,686. The impetus behind the resolution was growth in the periphery of the county which the board speculated would continue patterns of housing segregation, thus making it more difficult to maintain racial balance in the schools. Evidence presented at trial indicated that the ten percent rule was destined for failure because it was not possible to implement the rule and still “meet the 60-minute bus ride limit.” J.A. XXII-10,869. Nevertheless, extensive evidence was presented showing that CMS never sited schools in order to foster segregation and that “every effort was made to try to find school sites that would bring people together in balanced numbers.” J.A. VI-2752; see Meriwether County, 171 F.3d at 1337 (stating that “the absence of evidence indicating that racial motives played any part in the Board’s decisionmaking process” is relevant in accessing compliance with desegregation orders). For example, CMS’s executive director of planning and student placement testified that in siting schools CMS “looked at both African-American and all populations not only in the vicinity of the site, but in the entire district.” J.A. VII-2920. So dedicated was CMS to siting schools in integrated areas that it contemplated refusing a gift of land for school use because the land was in a predominantly white area. See J.A. V-1985. Faced with growth in the predominantly white regions of the far south and north, see J.A. XXXIII-16,261, CMS was compelled to serve populations in those areas via school sitings. CMS’s data show that in the late 1990s, student population was “growing at nearly 4,000 students per year,” J.A. XXIX-14,133, and consequently the board was “just trying to keep up” with the population explosion in building schools, J.A. V-2249. Overcrowding was a problem, and in the late 1990s “the average high school expected to operate at 109 percent of its capacity.” J.A. XXIX-14,-133. Even though CMS was forced to build schools at a rapid rate to serve an expanding student population, pupil assignment plans in which CMS described population growth as a “major consideration [ ]” are replete with efforts to improve racial balance. J.A. XXIX-14,133. For example, the 1997-98 assignment plan highlighted the creation and expansion of several magnet programs specially designed to reduce the black ratio in a number of schools. See J.A. XXIX-14,147-51. To the extent practicable, CMS did not sacrifice racial balance concerns to population growth. Though the two often pulled CMS in different directions, the record indicates that the board coordinated racial balance and school sitings as best it could under the circumstances. The evidence does not indicate that the abandonment of the ten percent rule or other decisions regarding school siting were the result of a desire to perpetuate the dual school system or circumvent the district court’s orders. CMS and the Swann plaintiffs, citing to prior orders, counter that the board has not done all that it could do in the area of school siting. Erection of such a standard, however, would effectively replace practicability with possibility. See Manning, 244 F.3d at 945 (observing that “the law does not require a defendant school board to take every conceivable step in attempting to desegregate”). The former implies measures that can be reasonably implemented under the circumstances, while the latter omits the reasonableness requirement. For instance, it was possible for CMS to adhere to the ten percent rule while ignoring growth in the far north and south of the county. Youngsters would have been compelled to ride buses for long periods while traveling with the flow of rush hour traffic, but it was nonetheless possible to adhere to the ten percent rule. Of course, the practicability of a refusal to respond to growth in Charlotte-Mecklen-burg is another matter. In the same vein, the Swann plaintiffs contend that school siting decisions were a response to white flight, which is an impermissible reason for failing to comply with a desegregation order. Growth, of course, is far different from flight. And experts offered evidence of “the economic boom in the Charlotte Metropolitan area in the last decade.” J.A. XXXIII-16,233. Charlotte-Mecklenburg is one of the most dynamic areas in the South; it is far different from the Charlotte-Mecklenburg of Swann, and much changed from that of Martin. In light of the growth in the county and a plethora of evidence demonstrating that the board used its best efforts to site schools in order to foster integration, the district court did not commit error when it concluded that there is no “continuing constitutional violation[ ] in the area of school siting.” Capacchione, 57 F.Supp.2d at 253. b. Burdens of Busing As for the burdens of busing, the district court found that in the most recent school year, 15,533 black students and 11,184 non-black students were bused for balancing purposes. Id. As stated earlier, traffic patterns make busing suburban students into the inner city far more difficult than busing inner-city children into the suburbs. See J.A. VI-2732; J.A. V-2228. Though a disproportionate number of African-American students are bused, the growth, housing patterns, and traffic patterns support the district court’s conclusion that the realities of the current situation should not block a unitary status determination. See Meriwether County, 171 F.3d at 1341 (finding no constitutional violation when white students are “somewhat less burdened by the transportation scheme” because of demographic factors). c. Student Transfers Finally, Martin’s concern with student transfers appears to have been based on the assumption that CMS would experience average growth. Courts are not omniscient, and the district court in 1979 could not have foreseen the changing demographics that would make student transfers the least of CMS’s worries. In the present litigation, the district court observed “that CMS ‘kept an eye on [magnet transfers] so that there wouldn’t be a run on the bank so to speak from any one school.’” Capacchione, 57 F.Supp.2d at 250 n. 10 (alteration in original). This finding is not clearly erroneous, nor can we discern the need for more findings on this issue in light of post-Martin changes. 3. Conclusion In sum, the district court’s findings on student assignment are “plausible in light of the record viewed in its entirety.” Anderson, 470 U.S. at 573, 105 S.Ct. 1504. The dual system of student assignment in CMS has been eradicated “to the extent practicable.” Dowell, 498 U.S. at 250, 111 S.Ct. 630. The imbalance existing in some schools is not traceable to the former dual system or to renewed discriminatory actions, but rather is a result of growth and shifting demographics. Consequently, we hold that the district court’s findings on student assignment are not clearly erroneous. B. Faculty Assignment In examining faculty assignment, the district court again used a plus/minus fifteen percent variance. Of the 126 schools operating in CMS, the district court found that in 1997-98 only ten schools were out of balance. The Swann plaintiffs point out that this number grew to sixteen in 1998-99, but this means that a mere twelve percent of the schools were out of balance. This is a far cry from the dual system in which “most of the 24,000 [black students] ha[d] no white teachers.” Swann, 300 F.Supp. at 1360. There is simply no evidence that CMS assigns black teachers to predominantly black schools and white teachers to predominantly white schools. Thus, the district court’s conclusion that this Green factor has been satisfied is not clearly erroneous. C. Facilities and Resources The Swann plaintiffs and CMS contend that the district court impermissibly shifted the burden of proof on this factor. As a result of the alleged error of law, CMS and the Swann plaintiffs contend that this issue must be remanded to the district court. This court has previously made clear that “once a court has found an unlawful dual school system, [those alleging the existence of racial disparities] are entitled to the presumption that current disparities are causally related to prior segregation, and the burden of proving otherwise rests on the defendants.” School Bd. of the City of Richmond v. Baliles, 829 F.2d 1308, 1311 (4th Cir.1987). In this case, however, the district court noted that none of the prior orders entered in the long history of the Swann litigation had ever found racial disparities to exist with regard to school facilities and concluded that CMS and the Swann plaintiffs bore the burden of establishing discrimination with regard to facilities. See Capacchione, 57 F.Supp.2d at 263 (“[I]t would defy logic to place now the burden of proof on the Plaintiff Interve-nors, requiring them to prove that vestiges of discrimination in facilities have been remedied, when the Court originally found no vestiges to exist.”). In our view, this erroneous assignment of the burden of proof, which did not affect the manner in which the parties tried the case or otherwise prejudice their rights, is harmless and does not undermine the district court’s factual conclusions regarding the facilities factor. Immediately after assigning the burden to CMS and the Swann plaintiffs, the district court’s order nonetheless summarized and weighed the facilities evidence presented by the parties. The district court carefully analyzed the testimony and report of Dr. Dwayne Gardner, an expert witness for CMS. Dr. Gardner analyzed seventy-three schools — every identifiably black school in CMS and a sampling of balanced schools and predominantly white schools. Dr. Gardner measured the adequacy, safety, healthfulness, accessibility, flexibility, efficiency, expansibility, and appearance of the schools. Based on the inspection he grouped schools as follows: “0-44 (suggests replacement), 45-59 (needs major improvement), 60-74 (needs minor improvement), 75-89 (serves program needs), and 90-100 (exceptional quality).” Id. at 264. The survey revealed that of the four schools that warranted replacement, two were majority white, and two were imbalanced black. See J.A. XXV-12,182-86. Thirty-four schools fell into the “needs major improvement” category, of which sixteen were imbalanced black and eighteen identifiably white. The district court determined that Dr. Gardner’s testimony established that any current disparities were functions of the age of the facilities at issue, because different building standards apply when a new facility is constructed as compared to when an older facility is renovated or upgraded. In other words, the renovation of an older facility usually complies with the code under which the facility was built. Because most facilities in the predominately black inner city are older while facilities in the predominately white suburbs are newer, the inference is that differences in building standards tend to affect black students disproportionately. This does not amount to racial discrimination. Indeed, this practice applies regardless of the racial composition of the school. Thus, older schools that are predominately white — several of which were built in the 1920s — are likewise affected by this practice. Capacchione, 57 F.Supp.2d at 265 (footnote and transcript references omitted). Thus, the district court concluded from Dr. Gardner’s testimony and report “that CMS’s facilities needs are spread across the system without regard to the racial composition of its schools.” Id. The district court also considered the testimony of CMS’s assistant superintendent of building services, who testified that out of 108 schools in need of renovations, eighty-one percent were racially balanced or identifiably white. See J.A. VIII-3810 & 3818. The district court concluded that this witness’s testimony likewise de