Full opinion text
MARCUS, Circuit Judge: At issue in this class action lawsuit is whether the City of Thomasville School District (“the District”) has satisfied its constitutional obligation to dismantle its former de jure racially segregated school system. The Plaintiffs — Shernika Holton and ten other representative parents of lack children attending elementary, mid-lie, and high schools operated by the District, and the Thomas County Branch of the NAACP — allege that the District has failed to do so, and request that judicial supervision of the District’s desegregation efforts be imposed. After a lengthy bench trial, the district court found that racial imbalances existed in several areas of the District’s operations, but that these imbalances were neither traceable to prior de jure segregation nor the result of present intentional discrimination. Accordingly, the district court concluded that the District had satisfied its constitutional obligation to desegregate. For the most part, we can discern no error in the district court’s findings of fact or its application of the law. However, as to the Plaintiffs’ claim that the District’s use of “ability grouping” to determine classroom assignments discriminates on the basis of race, we conclude that the district court failed to apply the legal standard long accepted in this Circuit, and that this legal error tainted its findings of fact. Accordingly, we affirm in part, reverse in part, and remand for reconsideration of the ability-grouping issue in light of the correct legal standard. I. Notably, this case differs from the other school desegregation cases that have come before us in recent years, in that the City of Thomasville School District has never operated under any court-imposed desegregation order or other court supervision. Indeed, this lawsuit is the first desegregation suit ever brought against the District. Because no court has ever imposed a desegregation order on the District, we face whether it is appropriate to do so for the first time now. Specifically, the Plaintiffs raise two broad causes of action. First, they claim that the District “has perpetuated, failed to disestablish and maintained purposefully racially segregated and unequal public schools ... and, thus, has acted contrary to the Fourteenth Amendment to the U.S. Constitution and 42 U.S.C. § 1983.” Second, they allege that the District “has perpetuated and failed to disestablish racially segregated public schools ..., has acted with the purpose and effect of subjecting Plaintiffs to discrimination in a federally funded program and, thus, has acted contrary to Title VI of the Civil Rights Act of 1964, 42 U.S.C. § 2000d, and implementing regulations at 34 C.F.R. Part 100.” The Plaintiffs seek a permanent injunction requiring the District to (a) disestablish its racially segregated school system; (b) adopt and implement a plan effectively to desegregate its buildings and classrooms; (c) provide equal educational facilities, resources, materials, and instruction to all students, and to provide compensatory instruction to students previously denied that opportunity; (d) cease all discriminatory imposition of discipline; and (e) desegregate all student activities, and cease discrimination against black students in this area. The district court certified a class of “all present and future parents or guardians of African American children enrolled or eligible to be enrolled within the Thomasville City School District.” Thomas County Branch of NAACP v. City of Thomasville Sch. Dist, 187 F.R.D. 690, 700 (M.D.Ga.1999). It later denied Defendant’s motions for summary judgment and to reconsider class certification. Thomas County Branch of NAACP v. City of Thomasville Sch. Dist., No. 6:98-CV-63, 2003 WL 169758, at *3 (M.D.Ga. Jan.21, 2003) (unpublished). In the same order, the district court granted Plaintiffs’ motion for partial summary judgment, finding that under Eleventh Circuit precedent, any present racial imbalances in the District are presumptively the result of the District’s previous de jure segregation. Id. at *2. Thereafter, the district court tried the case without a jury from July 21 to August 6, 2003. Based on the evidence presented, the trial judge made a series of detailed factual findings. We repeat just the basics here, as these findings are laid out with great clarity and detail in the district court’s order, dated February 5, 2004. See Thomas County NAACP. First, as background, the district court outlined the history of the District’s desegregation efforts, including numerous reorganizations of the District’s schools. At the time the Supreme Court issued its seminal opinion in Brown v. Bd. of Educ., 347 U.S. 483, 74 S.Ct. 686, 98 L.Ed. 873 (1954), declaring that racial segregation in public schools violated the Equal Protection Clause of the Fourteenth Amendment, the District was operating a de jure segregated school system. Until 1965, the District’s schools remained segregated, with two elementary schools (grades 1-6) serving black students and four serving white students, as well one high school (grades 7-12) for black students and another for white students. Following the passage of the Civil Rights Act of 1964, the District adopted its first desegregation plan, which became effective at the start of the 1965-66 school year. The plan was based upon freedom of choice, permitting parents to elect which school their children would attend. This method failed to accomplish any desegregation, and the District’s historically black schools remained all black. A series of exchanges between the District and the Department of Health, Education, and Welfare (“HEW”) ensued, culminating in the District’s adoption of a new desegregation plan in 1970. This plan created a single high school for all students in grades 9-12, regardless of race; a single middle school for all students in grades 7-8, regardless of race; a single school for all students in grade 6, regardless of race; a single school for all students in grade 5, regardless of race; and four elementary schools among which all students in grades 1-4 could select based on freedom of choice. The plan further provided that “[i]f the ‘freedom of choice’ plan does not eliminate the racial identifia-bility of each of the four elementary schools, alternate steps will be taken to give this assurance.” HEW found that the plan would accomplish the purposes of Title VI and accepted the plan on July 1, 1970. Some reconfiguration of the District’s schools occurred between 1970 and 1993, and by the start of the 1993-94 school year, the District was operating four elementary schools serving grades 1-5 (Douglass, Harper, Jerger, and Scott), one middle school serving grades 6-8 (McIntyre Park), and one high school for grades 9-12 (Thomasville High). At the end of the 2001-02 school year, Douglass Elementary School closed, and since then the District has maintained the remaining three elementary schools, as well as its single middle and high schools. After providing this background, the district court went on to make detailed findings of fact concerning racial imbalances in various areas of the District’s operations. The district court found racial imbalances to exist in these areas: the student populations of the District’s elementary schools; the composition of some individual classes within the District’s schools; the faculty assigned to the District’s elementary schools; the staff assigned to some of the District’s schools; the composition of the student population participating in the District’s gifted and special education programs; and possibly the number of students subjected to disciplinary actions. Regarding the first area — student populations of the District’s elementary schools — the district court found that two schools were “racially identifiable,” meaning that the percentage of black students enrolled varied more than twenty percent from the district-wide percentage of black students in the grades served by the school. Harper, the district court found, was an identifiably black school, whereas Jerger was an identifiably white school. In the school year 2002-03, for example, the district-wide percentage of black students was 73.6, while Harper’s student body was 98.5% black and Jerger’s was 39.8% black. Scott, the single non-racially identifiable elementary school, had a student population that was 90% black. The district court found, however, that these racial imbalances were not traceable in any proximate way to the District’s former de jure segregated school system. Notably, from 1970 (when the District adopted its second desegregation plan) until 1976, the black student population of at least three of the four elementary schools the District then operated “closely tracked the percentage of black students in-the District as a whole.” Thomas County NAACP, 299 F.Supp.2d at 1355. During that period, no student attended a school whose black student population varied by more than twenty percent from the district-wide percentage of black students. The district court supplied this table to illustrate the data: The racial imbalances that subsequently developed within the District’s schools, the district court found, were the result of pronounced enrollment and demographic changes in the school District. Following the implementation of the 1970 desegregation plan, the district court observed, white enrollment in the District’s schools declined substantially, while black enrollment remained fairly stable. From the 1970-71 school year to the 1977-78 school year, black students went from constituting 51.74% to 65.78% of the District’s enroll-ees. In addition, the City of Thomasville experienced population shifts during that period. In 1970, the City’s black population was concentrated primarily in the City’s southwestern sector, and since that time, the distribution of Thomasville’s black population has changed. For example, Harper Elementary School was “surrounded by some predominantly white communities” in 1970, but by 1980, that area had become almost entirely black, and by 1990, “there were few, if any, white students left in the area.” Id. at 1356 n. 19. As the neighborhoods ¿round Harper became increasingly black, so did Harper’s student population. The district court explained that “demographics overtook the Desegregation Plan,” so that Harper’s variance from the district-wide enrollment of black students went from 6% in 1970 to almost 20% in 1975. Id. at 1356. Meanwhile, the District’s other elementary schools varied by no more than 11% in this respect. The disparity at Harper came to the attention of HEW, and on May 13,1975, it sent a letter to the District’s Superintendent advising that the U.S. District Court for the District of Columbia had ordered it in Adams v. Weinberger, 391 F.Supp. 269 (D.D.C.1975), to put school districts on notice “to rebut or explain the substantial racial disproportion in one or more of the district’s schools.” HEW stated that “The court defined a racially disproportionate school as one in which a ‘20 percent disproportion exists between the percentage of local minority pupils in-the schools and the percentage in the entire school district.’ ” Several exchanges between the District and HEW followed, and the District explained its student assignment procedures to HEW in these terms: Assignments are based upon freedom of choice, modified only to the extent hereinafter stated. Freedom of choice forms are issued to all pupils each year. If a school reaches its capacity, priority is given to the child nearest the school. If a parent or student fails to return the form, the student is assigned by school officials to the school nearest the student’s home which has not been filled to capacity. In order to maximize a biracial complexion in the Harper School, freedom of choice is modified in two respects: (a) Whites residing in the Harper area have been required to attend Harper notwithstanding their selection of another school under freedom of choice[;] (b) Priority has been given to whites desiring to attend Harper as against blacks residing closer to that school. After receiving this explanation and other'information, HEW “determined that no further student desegregation is required of [the-District] at this time.” On November 17, 1975, HEW found the District “in compliance with Title VI of the Civil Rights Act of 1964 relative to assignment of students ... to schools.” However, HEW also noted that the situation at Harper warranted monitoring. Beginning in 1977, racial imbalances in the District’s elementary schools began gradually to increase. No formal plan was adopted by the District to address these imbalances, but in 1994, the District created a task force to consider the issue. The task force made consensus recommendations regarding a new process for assigning students to elementary schools. The District implemented these recommendations, with a few modifications, in 1995. The new assignment process is based primarily on parent preferences. If space does not permit accommodation of all preferences, a priority system based on special education considerations, sibling placement,, and residency, determines the assignment. Based on this history and data, the district court concluded that two elementary schools — Harper and Jerger — “are clearly racially identifiable schools.” Thomas County NAACP, 299 F.Supp.2d at 1358. To illustrate the data supporting this conclusion, the court supplied this table: Nevertheless, the court found, “that the racial composition of the District’s elementary schools is currently ‘imbalanced’ because of changes in the racial makeup of the City of Thomasville, shifting housing patterns, and changes in the enrollment of the District’s schools caused by declining white enrollment as compared to black enrollment.” Id. Moreover, the court found “that the current racial imbalances of the District’s elementary schools are not due to any intentional discrimination on the part of the District and are not vestiges of the District’s previous de jure racially segregated system.” Id. As to the second racially imbalanced area of the District’s operations — individual classes within its schools — the district court found the imbalances to be the result of the District’s use of “ability grouping” or “tracking” to assign students to classes. The District, the court explained, begins to group students into classes based on their perceived abilities as early as kindergarten. As a result, the court observed: Regrettably, a disproportionate number of low income children (most of whom happen to be black) are placed in the lower ability groups. The Court finds that these placements are not being made due to the race of the student. Many of these low income students are simply perceived as not being prepared when they first arrive at school. Due to their impoverished environment, they do not receive the background and support that is often so critical for being ready to learn. Tragically, it appears that for many of these children, the “die is cast” as early as kindergarten. These children do not appear to be reevaluated (and thus potentially “re-tracked”) during their progression through the system. The inevitable result therefore is that they remain on the “lower ability” track for the duration of their educational careers, absent parental intervention. Id. (footnotes omitted). The district court made “no finding as to whether some placements may be affected by the subtle racism of low expectations,” but concluded that the District does not manipulate the tracking system to track based on race, and that “intentional racial discrimination is not the reason for placement decisions.” Id. at 1358 n. 21. Regarding the third area of racial imbalance — the District’s faculty — the district court found that the imbalances were “not traceable in a proximate way to the District’s previous de jure segregated system.” Id. at 1360. The most recent available data, the district court observed, indeed showed racial imbalances within the faculty: Nevertheless, the court observed, the District made “remarkable progress” in desegregating its faculty following the implementation of its 1970 desegregation plan, so that for more than 10 years after-wards, no elementary school had a percentage of black faculty members that varied more than 15% from the district-wide percentage of black elementary faculty. Id. The court illustrated the data this way: Percentage of Black Faculty School Year District Balfour Scott Jerger Harper 1970-1971 44.2 42.9 43.5 31.3 45.5 1971-1972 43.4 46.2 36.4 37.5 45.5 1972-1973 47.3 46.2 42.1 40.0 54.5 1973-1974 43.2 42.9 36.8 35.3 41.7 1974-1975 45.7 42.9 36.8 41.2 54.5 1975-1976 41.1 40.0 40.0 41.2 45.5 1978-1979 41.1 35.7 42.9 37.5 38.5 1979-1980 43.3 40.9 35.3 46.2 1980-1981 39.3 36.4 39.1 35.3 42.9 1982-1983 36.2 30.8 43.5 35.3 35.7 Based on this data, the district court, found that “the District’s Desegregation Plan effectively desegregated the District’s faculty,” and that the faculty assignment system is and has been administered without regard to race. Id. Accordingly, the court concluded that existing racial imbalances were not traceable to prior de jure segregation. As to the fourth area of imbalance — the District’s staff — the district court found that based on the limited evidence presented regarding the race of the District’s elementary school principals and assistant principals, “any minimal imbalance that presently exists” was not proximately traceable to prior de jure segregation or the result of intentional discrimination. Id. at 1361. The 1970 desegregation plan, the district court found, “effectively desegregated the District’s staff’ by assigning principals in a manner that ensured all students would attend at least one school with a white principal and at least two schools with a black principal. Id. As to the fifth imbalanced area — the District’s gifted program for high-performing students — the district court observed black students were “arguably” underrepresented in the program. Id. at 1362. However, the court found that placement in the gifted program was governed by statewide eligibility requirements, that no student had been admitted to the program without satisfying these requirements, and that no student satisfying the requirements had ever been denied the opportunity to participate on the basis of race or otherwise. Accordingly, the court concluded that racial imbalances in the District’s gifted program were not proximately traceable to the District’s prior de jure segregation, nor were they the result of present intentional discrimination. Regarding the sixth area of imbalance— the district’s special education program— the district court again found that black students were “arguably” overrepresented. Id. The program, the district court observed, was governed by myriad state and federal regulations — including rules issued by the Georgia Department of Education and procedures outlined in the Individuals with Disabilities Act, 20 U.S.C. § 1400 et seq. — with which the District reasonably complied. Specifically, the court found no evidence that any student had been placed in special education unless state and federal requirements were satisfied, and no evidence that race had ever been a factor in a placement decision. Accordingly, the’ court concluded that any racial imbalance was not proximately traceable to de jure segregation. As to the final imbalanced area — administration of discipline — the district court assumed without deciding that black students were disproportionately subjected to disciplinary action, concluding nevertheless that the District did not treat black students differently from white students in disciplining them. The court found no evidence that a black student had ever received a harsher punishment than a white student for similar misconduct or that a black student had ever received a referral for punishment where a white student did not under the same or similar circumstances. The district court found that race had not been a factor in any disciplinary decision, and that any racial imbalance in the administration of discipline was not proximately traceable to past de jure segregation. In addition, the district court examined several other facets of the Thomasville school system where it found no racial imbalances present: the District’s facilities, transportation services, and extracurricular activities. As to facilities, the court found no disparity in the facility quality or resources of the District’s identifiably black schools as compared to its identifiably white school, and concluded that race played no role in the District’s allocation of funds to the various schools. Regarding transportation, the district court observed that the only transportation the District offered was for special education and extracurricular activities, as well as a very limited route implemented after the closing of Douglass Elementary to transport students previously enrolled there to Harper Elementary. The court concluded that because Douglass’ student body had been 100% black, only black students received transportation, and thus the District did not discriminate against black students in the provision of transportation. Regarding extracurricular activities, the court found that all of the District’s extracurric-ulars were available to all students without regard to race, and that no racial imbalances existed within those programs. Based on these findings, the district court ruled in favor of the District, concluding that although racial imbalances existed in some aspects of the District’s schools, they were neither traceable to the District’s prior de jure segregation, nor the result of present intentional discrimination. The district court’s judgment, dated February 6, 2004, directed that each side would bear its own costs. II. The Plaintiffs raise five broad issues on appeal. First, they argue that the district court’s failure to determine whether the District had achieved “unitary status” constitutes reversible error. Second, the Plaintiffs claim that the district court misapplied the so-called “Keyes” presumption that present racial imbalances within a previously de jure segregated school system are a result of prior segregation, because the burden of proof it placed on the District to rebut the presumption was too low in several respects. Third, the Plaintiffs say that the district court failed to scrutinize with sufficient rigor the District’s use of “ability tracking” to assign students to classes. Fourth, the Plaintiffs contend that the district court failed to articulate or apply any standard for intentional discrimination. Finally, Plaintiffs suggest that the district court’s legal errors infected its factual findings, and that the court made several findings of fact that were clearly erroneous. In school desegregation cases, we review de novo the district court’s interpretation and application of the law. NAACP, Jacksonville Branch v. Duval County Sch., 273 F.3d 960, 965 (11th Cir.2001) (“Jacksonville NAACP”); Manning ex rel. Manning v. Sch. Bd., 244 F.3d 927, 940 (11th Cir.2001). However, insofar as the Plaintiffs ask us to review the district court’s factual findings, we do so only for clear error. Fed.R.Civ.P. 52(a); Jacksonville NAACP, 273 F.3d at 965; Manning, 244 F.3d at 940. A. We begin with a brief overview of the applicable law of school desegregation. The Supreme Court’s decisions in Brown v. Bd. of Educ., 347 U.S. 483, 74 S.Ct. 686, 98 L.Ed. 873 (1954) (“Brown I”), and Brown v. Bd. of Educ., 349 U.S. 294, 75 S.Ct. 753, 99 L.Ed. 1083 (1955) (“Brown II”), placed all de jure segregated school systems under a constitutional obligation to desegregate. See, e.g., Green v. County Sch. Bd., 391 U.S. 430, 435-37, 88 S.Ct. 1689, 20 L.Ed.2d 716 (1968) (“[S]chool boards operating [dual] school systems were required by Brown II ‘to effectuate a transition to a racially nondiscriminatory school system.’ ... Brown II was a call for the dismantling of well-entrenched dual systems .... ”). The Supreme Court has explained this affirmative obligation in these terms: “The duty and responsibility of a school district once segregated by law is to take all steps necessary to eliminate the vestiges of the unconstitutional de jure system. This is required in order to ensure that the principal wrong of the de jure system, the injuries and stigma inflicted upon the race disfavored by the violation, is no longer present.” Freeman v. Pitts, 503 U.S. 467, 485, 112 S.Ct. 1430, 118 L.Ed.2d 108 (1992); see also, e.g., Swann v. Charlotte-Mecklenburg Bd. of Educ., 402 U.S. 1, 15, 91 S.Ct. 1267, 28 L.Ed.2d 554 (1971) (explaining that formerly dual school systems are “clearly charged with the affirmative duty to take whatever steps might be necessary to convert to a unitary system in which racial discrimination would be eliminated root and -branch” (quoting Green, 391 U.S. at 437-38, 88 S.Ct. 1689)). A school district’s obligation is to eliminate the vestiges of past discrimination “to the extent practicable.” Manning, 244 F.3d at 943 (quoting Lockett v. Bd. of Educ., 111 F.3d 839, 842 (11th Cir.1997)). However, our Court and the Supreme Court have both explicitly rejected the notion that school systems must eliminate vestiges of discrimination “to the maximum extent practicable.” See, e.g., Missouri v. Jenkins, 515 U.S. 70, 101, 115 S.Ct. 2038, 132 L.Ed.2d 63 (1995) (explaining that the proper judicial inquiry is whether the district has remedied vestiges of de jure segregation “to the extent practicable,” not to the “maximum potential”); Manning, 244 F.3d at 943. Judicial authority may be invoked when a school district -fails to fulfill this duty: “If school authorities fail in their affirmative obligations under [Brown I, Brown II, and Green], judicial authority may be invoked. Once a right and a violation have been shown, the scope of a district court’s equitable powers to remedy past wrongs is broad, for breadth and flexibility are inherent in equitable remedies.” Swann, 402 U.S. at 15, 91 S.Ct. 1267.. However, “[i]n seeking to define ... how far this remedial power extends it is important to remember that judicial powers may be exercised only on the basis of a constitutional violation. Remedial judicial authority does not put judges automatically in the shoes of school authorities whose powers-are plenary. Judicial authority enters only when local authority defaults.” Id. at 16, 91 S.Ct. 1267. Accordingly, in deciding whether judicial supervision may properly be imposed in this case, the key consideration is whether the District has met its obligation to eliminate the vestiges of its dual school system “to the extent practicable.” In determining whether past discrimination has been sufficiently eradicated, the Supreme Court has advised, courts must examine a number of specific facets of a school system: its faculty, staff, transportation, extracurricular activities, and facilities. Green, 391 U:S. at 435, 88 S.Ct. 1689. These areas, “in addition to student attendance patterns, must be free from racial discrimination before the mandate of Brown is met.” Freeman, 503 U.S. at 486, 112 S.Ct. 1430. These so-called “Green factors,” the Court has explained, “are a measure of the racial identifiability of schools in a system that is not in compliance with Brown.” Id. In determining whether the school district has eliminated vestiges of de jure segregation to the extent practicable in those six areas, “a critical beginning point is the degree of racial imbalance in the school district, that is to say a comparison of the proportion of majority to minority students in individual schools with the proportions of the races in the district as a whole.” Id. at 474, 112 S.Ct. 1430. In historically segregated school systems, the Supreme Court has held, “where it is possible to identify a ‘white school’ or a ‘Negro school’ simply by reference to the racial composition of teachers and staff, the quality of school buildings and equipment, or the organization of sports activities, a prima facie case of violation of substantive constitutional rights under the Equal Protection Clause is shown.” Swann, 402 U.S. at 18, 91 S.Ct. 1267. The burden then shifts to the school district to demonstrate that the racial imbalances are “not the result of present or past discriminatory action on their part.” Id. at 26, 91 S.Ct. 1267; accord Freeman, 503 U.S. at 494, 112 S.Ct. 1430 (holding that in a formerly de jure segregated school system, “[t]he school district bears the burden of showing that any current imbalance is not traceable, in a proximate way, to the prior violation”); Jacksonville NAACP, 273 F.3d at 966; Manning, 244 F.3d at 942. One way for the school district to meet its burden is by showing that the racial imbalances are attributable to demographic forces. The Supreme Court has explained that “[a]s the de jure violation becomes more remote in time and ... demographic changes intervene, it becomes less likely that a current racial imbalance in a school district is a vestige of the prior de jure system.” Freeman, 503 U.S. at 496, 112 S.Ct. 1430. Accordingly, “[o]nce the racial imbalance due to the de jure violation has been remedied, the school district is under no duty to remedy imbalance that is caused by demographic factors.” Id. at 494, 112 S.Ct. 1430; accord Swann, 402 U.S. at 31-32, 91 S.Ct. 1267 (“Neither school authorities nor district courts are constitutionally required to make year-by-year adjustments of the racial composition of student bodies once the affirmative duty to desegregate has been accomplished and racial discrimination through official action is eliminated from the system. This does not mean that federal courts are without power to deal with future problems; but in the absence of a showing that either the school authorities or some other agency of the State has deliberately attempted to fix or alter demographic patterns to affect the racial composition of the schools, further intervention by a district court should not be necessary.”). If the school district can demonstrate that demographic factors have “substantially caused” the racial imbalances in its schools, “it overcomes the presumption that segregative intent is the cause, and there is no constitutional violation.” Jacksonville NAACP, 273 F.3d at 966; accord Manning, 244 F.3d at 944. The school district need not prove that demographics are the sole cause of the imbalances. As we have explained previously, “a plaintiff does not undermine the strength of a defendant’s demographic evidence by merely asserting that demographics alone do not explain the racial imbalances. Rather, for a plaintiff to preserve the presumption of de jure segregation, the plaintiff must show that the demographic shifts are the result of the prior de jure segregation or some other discriminatory conduct.” Id. at 944-45 (footnote omitted). B. With this legal framework in mind, we turn now to each of the arguments the Plaintiffs have raised on appeal. 1. The Plaintiffs’ first claim is that the district court erred in failing to determine whether the District had achieved “unitary status.” Indeed, the district court explicitly declined to make such a determination, explaining: “To avoid confusing terminology, the Court has refrained from using the terms ‘unitary’ or ‘unitary status’ in describing its findings and conclusions in this case.” Thomas County NAACP, 299 F.Supp.2d at 1366 n. 30. However, the district court’s decision not to make such a finding was not error, for two reasons. First, an assessment of unitary status is generally only made when a district court is deciding “when it is appropriate to restore local control” (ie., to end judicial supervision) of . a school system. See Manning, 244 F.3d at 942. This much is evident from the two factors courts consider in making the unitariness determination: (1) “whether local authorities have eliminated the vestiges of past discrimination to the extent practicable,” and (2) “whether local authorities have in good faith fully and satisfactorily complied with, and shown a commitment to, the desegregation plan.” Id. In a case such as this one — where the school district has never been placed under judicial supervision — the second prong of the inquiry has no application, since no desegregation plan has ever been imposed on the district. Second, and more important, the Supreme Court and this Court have made clear that the substance of the judicial inquiry, not the terminology employed, is what matters. The usefulness of the terms “unitary” and “unitary status” has been called into question, and in fact the Supreme Court has urged the lower courts to discard these terms, explaining: The lower courts have been inconsistent in their use of the term “unitary.” Some have used it to identify a school district that has completely remedied all vestiges of past discrimination. Under that interpretation of the word, a unitary school district is one that has met the mandate of [Brown and Green], Other courts, however, have used “unitary” to describe any school district that has currently desegregated school assignments, whether or not that status is solely the result of a court-imposed desegregation plan. In other words, such a school district could be called unitary and nevertheless still contain vestiges of past discrimination. That there is such confusion is evident in Georgia State Conference of Branches of NAACP v. Georgia, 775 F.2d 1403 (C.A.11 1985), where the Court of Appeals drew a distinction between a “unitary school district” and a district that has achieved “unitary status.” Bd. of Educ. v. Dowell, 498 U.S. 237, 245, 111 S.Ct. 630, 112 L.Ed.2d 715 (1991) (citations omitted). Accordingly, the Supreme Court explained that “it is a mistake to treat words such as ‘dual’ and ‘unitary’ as if they were actually found in the Constitution. The constitutional command of the Fourteenth Amendment is that ‘[n]o State shall ... deny to any person ... the equal protection of the laws.’ ” Id. at 245-46, 111 S.Ct. 630; see also Freeman, 503 U.S. at 487, 112 S.Ct. 1430. This obligation, not whether a school district may be labeled “unitary,” is the proper focus of judicial inquiry. In Lee v. Etowah County Bd. of Educ., 963 F.2d 1416 (11th Cir.1992), we similarly observed that “[m]uch confusion has arisen from the use of the terms ‘unitary’ and ‘unitary status.’ ” Id. at 1419 n. 3. We therefore declared: “To minimize confusion, we discourage the future use of the term ‘unitary’ to describe a system that has not eliminated vestiges of past discrimination to the extent practicable but is merely currently in compliance with a court-imposed desegregation plan .... ” Id. Thus, when the plaintiffs in Lee “complain[ed] that the district court should have used the phrase ‘unitary status’ rather than the phrase ‘unitary system,’ ” the Court stated: “The district court’s opinion makes clear that it found that the defendants had eliminated the vestiges of their prior discrimination; thus, it is wholly irrelevant what precise language the district court used to announce its findings.” Id. at 1424 n. 9. Mindful of the Supreme Court’s direction that “[sjubstance, not semantics, must govern” in remedying school segregation, Swann, 402 U.S. at 31, 91 S.Ct. 1267, we hold that the district court committed no error by declining to make a finding of “unitary status.” 2. The Plaintiffs’ second argument on appeal is that the district court misapplied the so-called “Keyes” presumption that present racial imbalances within a previously de jure segregated school system are proximately traceable to prior segregation, by placing too low a burden of proof on the District to rebut the presumption. Specifically, the Plaintiffs argue that the district court erred in three ways: it failed to hold the District to its obligation to eliminate the vestiges of segregation to the extent practicable; it failed to require the District to show that its own policies were not factors contributing to its racial imbalances; and it failed to require the District to show that demographic changes were the “substantial” cause of the racial imbalances. As to the first argument, the Plaintiffs suggest that the district court erroneously failed to require the District to present evidence that it had eliminated the vestiges of segregation to the extent practicable — that is, that the District had taken “every reasonable effort ... to eradicate segregation and its insidious residue.” Appellants’ Br. at 23 (quoting Jacksonville NAACP, 273 F.3d at 973). Essentially, the Plaintiffs’ argument is that the district court failed to consider the substance of the unitariness analysis. The Plaintiffs are correct that the essence of a school district’s desegregation duty is to eliminate the vestiges of segregation “to the extent practicable,” and that the district court neglected to use this precise terminology in assessing whether the District had fulfilled its obligation. Nevertheless, we can find no reversible error here, since the district court’s thorough opinion and detailed findings plainly illustrate that the court got the substance , of the inquiry-right. A district court may impose court supervision of a school district’s desegregation efforts “only insofar as it advances the ultimate objective of alleviating the initial constitutional violation.” Freeman, 503 U.S. at 489, 112 S.Ct. 1430. Accordingly, in considering whether to place a school district under judicial supervision, the proper focus of a district court’s inquiry is on whether a constitutional violation exists — that is, whether the district has failed to meet its constitutional obligation to desegregate its schools to the extent practicable. See, e.g., Swann, 402 U.S. at 16, 91 S.Ct. 1267. We have instructed the district courts that, in evaluating whether a school district has “[met] its constitutional obligation to eliminate the vestiges of de jure segregation to the extent practicable,” a court must examine the six areas of the school system enumerated in Green, applying the “presumption that any current racial disparities in these areas are the result of [the district’s] past unlawful conduct.” Jacksonville NAACP, 273 F.3d at 966. The school district “bears the burden of showing that any current imbalance [in these areas] is not traceable, in a proximate way, to the prior violation.” Id. (alteration in original) (quoting Freeman, 503 U.S. at 493, 112 S.Ct. 1430). Our case law establishes that if the school district proves that demographic shifts have substantially caused any current racial imbalances in the school system, it will have satisfied its constitutional obligation to eliminate the vestiges of segregation, to the extent practicable: “If a school board can prove that [demographic or other external] factors have substantially caused current racial imbalances in its schools, it overcomes the presumption that segregative intent is the cause [of any racial imbalance], and there is no constitutional violation. Where there is no constitutional violation, a school board is under no duty to remedy racial imbalances.” Id. (citations omitted). Here, the district court repeatedly emphasized that the District was constitutionally obligated to desegregate its schools, see, e.g., Thomas County NAACP, 299 F.Supp.2d at 1343-51, 1366,. but did not explicitly acknowledge that the nature of the obligation was to eliminate the vestiges of segregation “to the extent practicable”; accordingly, the district court never explicitly determined whether the District had satisfied this obligation. In spite of its failure to use the most precise words, the district court got the substance of the inquiry right. Heeding the Supreme Court’s directive that judicial authority may not be invoked unless local authority has defaulted on its obligation to remedy a constitutional violation, see Swann, 402 U.S. at 16, 91 S.Ct. 1267, the district court focused its inquiry on whether any unremedied constitutional violation lingered in the Thomasville school district. Since the District had previously operated a de jure segregated school system, the district court observed first that the proper consideration was “whether any vestiges of the previous de jure system still exist.” Thomas County NAACP, 299 F.Supp.2d at 1366. To make this determination, the district court evaluated at some length each of the Green factors (which, again, include student assignments, facilities, faculty and staff assignments, transportation, and extracurricular activities), as well as the District’s curriculum and class assignments, gifted and special education programs, and discipline system, to determine whether racial imbalances were present in any of these areas. See id. at 1352 & n. 14. Invoking the so-called Keyes presumption, the district court observed that any such imbalances must be “presumed to be vestiges of the previous de jure segregated system.” Id. at 1352. Identifying racial imbalances in a number of the Green and other areas (elementary school student population; individual classes; faculty assignments; staff assignment; gifted and special education programs; and disciplinary actions), the court went on to “examine[ ] each of these areas to determine whether the District has carried its burden of proof by proving by a preponderance of the evidence that these racial imbalances are not traceable in a proximate way to the District’s previous de jure segregated system.” Id. at 1354; see also id. at 1366. For each imbalanced area, the district court unambiguously found that demographic and other external factors — including “changes in the racial makeup of the City of Thomasville, shifting housing patterns, and changes in the enrollment of the District’s schools caused by declining white enrollment as compared to black enrollment” — were the cause of the imbalance. Id. at 1358. Upon determining that the District had carried its burden in a particular area, the trial court then asked “whether the District presently engages in purposeful racial discrimination” in that area. Id. at 1366. The district court found each area of the Thomasville school system to be free of intentional racial discrimination. Finally, the district court concluded that “the District carried its burden of proving that the racial imbalances in [certain] areas were not traceable in a proximate way to its previous de jure segregated system,” and that “current purposeful discrimination did not proximately cause these imbalances.” Id. at 1367. “[S]inee these imbalances are not vestiges of the previous de jure segregated system and are not the proximate result of presently practiced racial discrimination, they do not support a claim under either the Fourteenth Amendment or Title VI.” Id.; see also id. at 1352. In substance, the district court’s analysis tracked precisely the methodology prescribed by the Supreme Court and this Court for determining whether a school district has fulfilled its constitutional obligation to desegregate. In concluding that racial imbalances within the Thomasville school system were traceable not to any historical segregation but rather to demographic and other external forces, the district court necessarily found that the District had eliminated the vestiges of segregation “to the extent practicable.” Quite simply, the district court’s failure to employ the term “to the extent practicable” does not amount to reversible error. Next, the Plaintiffs suggest that the District’s burden of rebutting the presumption of continuing segregation required it to demonstrate that “its policies and practices with respect to schoolsite location, school size, school renovations and additions, student-attendance zones, student assignment and transfer options, mobile classroom units, transportation of students, assignment of faculty and staff, etc., considered together ... were not factors in causing the existing condition of segregation in these schools.” Appellants’ Br. at 28 (quoting Keyes, 413 U.S. at 213-14, 93 S.Ct. 2686). The Plaintiffs have taken this standard out of context. For one thing, it derives from Keyes, which, as we noted earlier, dealt with a school system that was not statutorily segregated. The standard the Plaintiffs quote lays out the burden a school district faces in rebutting the presumption that an entire unified school system is infected with intentional segregation, which arises out of a finding of intentional segregation in a single school within that system. See Keyes, 413 U.S. at 213-14, 93 S.Ct. 2686. The presumption is not applicable here, since Thomas-ville operated a school system that was concededly segregated in its entirety under Georgia law. Second, even if that presumption was applicable in this case, the Plaintiffs, we think, have omitted with an ellipsis a crucial aspect of the standard. The district’s burden is to prove that its policies and practices “either were not taken in effectu-ation of a policy to create or maintain segregation in the core city schools, or, if unsuccessful in that effort, were not factors in causing the existing condition of segregation in these schools.” Id. at 214, 93 S.Ct. 2686 (emphasis added). All the former component requires the school district to prove is that its policies and practices were not intentionally discriminatory. Only if the school district is unable to do so is it required to demonstrate that its policies “were not factors” in creating segregated conditions. In this case, the district court concluded that the District’s policies and practices were not intentionally discriminatory, and therefore the court had no occasion to consider whether these policies were “factors” contributing to racial imbalances in Thomasville schools. Third, our Court and the Supreme Court have repeatedly defined the burden that a formerly de jure ségregated school district must carry not as the Keyes-de-rived standard Plaintiffs favor, but rather the standard employed by the district court: “The school district bears the burden of showing that any current [racial] imbalance is not traceable, in a proximate way, to the prior violation.” Freeman, 503 U.S. at 494, 112 S.Ct. 1430; accord, e.g., Manning, 244 F.3d at 942; Jacksonville NAACP, 273 F.3d at 966. The district court’s opinion illustrates that this was exactly the burden to which it held the District. See, e.g., Thomas County NAACP, 299 F.Supp.2d at 1352 (“The Court ... finds that any racial imbalances that presently exist within the District are not traceable in a proximate way to the de jure racially segregated system that existed at the time Brown I was decided almost fifty years .ago. The Court does find that racial imbalances presently exist within the District in certain areas. Under Keyes these racial imbalances are presumed to be vestiges of the previous de jure segregated system. However, as set forth hereinbelow, the Court finds that the District carried its burden of proof by rebutting that presumption.”); id. at 1366 (“For those areas in which the Court has found current racial imbalances, there is a presumption that those racial imbalances are vestiges of the District’s. previous -de jure segregated system, and Defendant bears the burden of rebutting that presumption by proving by a preponderance of the evidence that the racial imbalances are not traceable in a proximate way to the previous de jure segregated system.”). The district court therefore held the City of Thomasville School District to the appropriate burden, and committed no error in declining to place on the District the burden of demonstrating that its policies and practices were not factors contributing to the racial imbalances within its schools. Finally, the Plaintiffs argue that the district court erred by failing to require the District to show that demographics were the “substantial” cause of the racial imbalances in its student population. The Plaintiffs concede that a school district may overcome the presumption that racial imbalances are attributable to past de jure segregation by demonstrating that they were instead caused by demographic shifts, but they maintain that the District’s showing in this case was inadequate, since the district court did not find that demographics constituted a substantial cause of those imbalances. Because the district court’s careful analysis reveals that it unambiguously did find demographics to be the substantial cause of the racial imbalances in the student populations of certain Thomasville elementary schools, we can discern no error. We have repeatedly observed that one way for a school district to rebut the presumption that racial imbalances are attributable to past segregation is to “prove that [demographic shifts or other external forces] have substantially caused current racial imbalances in its schools.” Jacksonville NAACP, 273 F.3d at 966. Indeed, the Supreme Court has explained that efforts to counteract the effects of demographic shifts are simply beyond the scope of judicial authority: The effect of changing residential patterns on the racial composition of schools, though not always fortunate, is somewhat predictable. Studies show a high correlation between residential segregation and school segregation .... Where resegregation is a product not of state action but of private choices, it does not have constitutional implications. It is beyond the authority and beyond the practical ability of the federal courts to try to counteract these kinds of continuous and massive demographic shifts. To ’attempt such results would require ongoing and never-ending supervision by the courts of school districts simply because they were once de jure segregated. Residential housing choices, and their attendant effects on the racial composition of schools, present, an ever-changing pattern, one difficult to address through judicial, remedies. Freeman, 503 U.S. at 495, 112 S.Ct. 1430. After discussing at considerable length the Supreme Court’s precedents to this effect, see Thomas County NAACP, 299 F.Supp.2d at 1349-50, the district court conducted a detailed analysis of the effect of demographic shifts on the student populations of Thomasville’s elementary schools. Laying out the pertinent data in table form, the district court explained that for the first six years after the District adopted its 1970 desegregation plan, the racial composition of each of the District’s schools “closely tracked” the racial composition of the District as a-whole. Id. at 1355. Nevertheless, the district court explained: “After the Desegregation Plan was implemented, the number of white students enrolled in the District declined substantially over a period of several years. Meanwhile, black enrollment remained fairly stable.” Id, at 1356 (citations omitted). The court supplied data for the eight-year period from 1970-1978 illustrating this change in the racial composition of the District’s student body: Then, the district court explained: “In addition to changes in school enrollment, the City of Thomasville also experienced population shifts after the implementation of the Desegregation Plan. In 1970, the black population in the City was concentrated primarily in the City’s southwestern sector. Since that time, the distribution of the black population throughout Thomas-ville has changed.” Id. (citations omitted). As an example, the court explained that “in 1970, Harper Elementary School was surrounded by some predominantly white communities. As the neighborhoods around Harper became increasingly black, so did Harper’s student population. Because of changes in the black population of the District and the City of Thomasville, demographics overtook the Desegregation Plan and Harper’s enrollment became increasingly black.” Id. (citations and footnotes omitted). Indeed, “Harper’s variance from the district-wide percentage of black students went from approximately 6% in 1970 to almost 20% in 1975, while the other elementary schools’ black enrollment during that period varied no more than 11% from The district-wide black enrollment for the elementary grades.” Id. In addition, the district court noted, “[b]y 1980 the area around Harper had become almost entirely black and by 1990 there were few, if any, white students left in the area.” Id. at 1356 n. 19. Based on this analysis, the district court concluded that demographic changes, not prior de jure segregation or present intentional discrimination, were responsible for the racial imbalances in the District’s elementary school populations: Based upon the evidence presented at trial, the Court finds that the racial composition of the District’s elementary schools is currently “imbalanced” because of changes in the racial makeup of the City of Thomasville, shifting housing patterns, and changes in the enrollment of the District’s schools caused by declining white enrollment as compared to black enrollment. The Court finds that the current racial imbalances of the District’s elementary schools are not due to any intentional discrimination on the part of the District and are not vestiges of the District’s previous de jure racially segregated system. Id. at 1358. Although the district court did not explicitly say that demographic changes were the “substantial” cause of the racial imbalances, it clearly found that the imbalances existed “because of’ such changes, and that they were “not due to” any current intentional discrimination or past de jure segregation. The court’s findings therefore unmistakably indicate that it found demographic shifts to be the substantial cause of the racial imbalances in Thomas-ville schools. Insofar as the Plaintiffs are saying that the district court did not find demographics to be the sole cause of these imbalances, this simply is not the burden that the District bears. As we observed earlier, “a plaintiff does not undermine the strength of a defendant’s demographic evidence by merely asserting that demographics alone do not explain the racial imbalances. Rather, for a plaintiff to preserve the presumption of de jure segregation, the plaintiff must show that the demographic shifts are the result of the prior de jure segregation or some other discriminatory conduct.” Manning, 244 F.3d at 944^15 (footnote omitted). The Plaintiffs in this case have made no such showing, and thus the district court committed no error in concluding that the District had carried its burden by demonstrating that demographic changes, not past segregation or present intentional discrimination, were responsible for the racial imbalances in the student bodies of District schools. 3. The Plaintiffs’ third argument on appeal is that in analyzing the constitutionality of the District’s “ability-grouping” or “tracking” practices, the district court failed to apply this Circuit’s precedent, which permits tracking only when it “is not based on the present results of past segregation or will remedy such results through better educational opportunities.” Ga. State Conference of Branches of NAACP v. Georgia, 775 F.2d 1403, 1414 (11th Cir.1985) (“Ga. NAACP”)(quoting McNeal v. Tate County Sch. Dist., 508 F.2d 1017, 1020 (5th Cir.1975)). On this point, we agree with the Plaintiffs that the district court failed to apply the Circuit’s well-settled standard, and that this constitutes reversible error. Although ability-grouping practices may have the effect of creating racial imbalances within classrooms, we have “consistently stated that ability grouping is not per se unconstitutional.” Castaneda v. Pickard, 648 F.2d 989, 994 (5th Cir. June 23, 1981). As the Plaintiffs have observed, such practices are permissible in spite of any segregative effect they,may have if the assignment method “is not based on the present results of past segregation or will remedy such results through better educational opportunities.” McNeal, 508 F.2d at 1020; see also, e.g., Ga. NAACP, 775 F.2d at 1414; Quarles v. Oxford Mun. Separate Sch. Dist, 868 F.2d 750, 753-54 (5th Cir.1989). In this case, the district court found that the District’s use of ability-grouping created racial imbalances within many of the district’s individual classes. Specifically, the court found overrepresentation of black students in less academically advanced classes and overrepresentation of white students in more academically advanced classes. These imbalances, the court concluded, were “a result of the District’s educational policy of ‘ability grouping’ or ‘tracking.’ ” Thomas County NAACP, 299 F.Supp.2d at 1358. However, the district court did not ask whether the District’s ability-grouping practices satisfied our long-established requirement that the tracking policy either not be based on present results of past discrimination or be designed to remedy such results. Instead of determining whether the District’s ability-grouping policy was based on present results of past segregation or whether it would remedy such results, the district court focused on whether the tracking practice was intentionally discriminatory. The court acknowledged that “the District’s tracking system has had the effect of creating racially imbalanced classes within the District’s schools,” but determined that “it was not the intention of the tracking system to segregate students based upon race” and that “the District does not manipulate the ability tracking system in order. to track students based upon their race.” Id. at 1359. To pass any further judgment on the District’s tracking policy, the court determined, was “beyond the realm of expertise of the judicial branch,” and best left to educators. Id. at 1358 n. 22. However, whether a school district’s ability-grouping practices are based on present results of past discrimination, and whether they will remedy such results, are well-settled subjects of judicial inquiry, since they go to the constitutionality — not the soundness as a policy matter — of these practices. See, e.g., McNeal, 508 F.2d at 1020; Ga. NAACP, 775 F.2d at 1414; Castaneda, 648 F.2d at 996-97 (“The merits of a program which places students in classrooms with others perceived to have similar abilities are hotly debated by educators; nevertheless, it is educators, rather than courts, who are in a better position ultimately to resolve the question whether such a practice is, on the whole, more beneficial than detrimental to the students involved. Thus, as a general rule, school systems, are free to employ ability grouping, even when such a policy has a segregative effect, so long, of course, as such a practice is genuinely motivated by educational concerns and not discriminatory motives.” (emphasis added)). The district court’s failure to conduct the proper inquiry requires us to remand this issue for the district court to reconsider the constitutionality of the District’s ability-grouping practices, applying the legal framework established by our Circuit’s precedents in McNeal and Georgia NAACP. Because “[p]roper resolution of any desegregation case turns on a careful assessment of its facts,” Freeman, 503 U.S. at 474, 112 S.Ct. 1430, we will not decide for ourselves whether the District’s use of tracking passes muster under this standard, but rather afford the trier of fact the first opportunity to do so. 4. The Plaintiffs’ fourth claim on appeal is that the district court failed to articulate any standard for determining whether the District engaged in present intentional discrimination, and that the court should have asked whether race was a substantial motivating factor in the District’s actions. Appellants’ Br. at 35 (citing Vill. of Arlington Heights v. Metro. Hous. Dev. Corp., 429 U.S. 252, 265-66, 97 S.Ct. 555, 50 L.