What follows is an opinion from the Supreme Court of the United States. Your task is to determine the bases on which the Supreme Court rested its decision with regard to the legal provision that the Court considered in the case. Consider "judicial review (national level)" if the majority determined the constitutionality of some action taken by some unit or official of the federal government, including an interstate compact. Consider "judicial review (state level)" if the majority determined the constitutionality of some action taken by some unit or official of a state or local government. Consider "statutory construction" for cases where the majority interpret a federal statute, treaty, or court rule; if the Court interprets a federal statute governing the powers or jurisdiction of a federal court; if the Court construes a state law as incompatible with a federal law; or if an administrative official interprets a federal statute. Do not consider "statutory construction" where an administrative agency or official acts "pursuant to" a statute, unless the Court interprets the statute to determine if administrative action is proper. Consider "interpretation of administrative regulation or rule, or executive order" if the majority treats federal administrative action in arriving at its decision.Consider "diversity jurisdiction" if the majority said in approximately so many words that under its diversity jurisdiction it is interpreting state law. Consider "federal common law" if the majority indicate that it used a judge-made "doctrine" or "rule; if the Court without more merely specifies the disposition the Court has made of the case and cites one or more of its own previously decided cases unless the citation is qualified by the word "see."; if the case concerns admiralty or maritime law, or some other aspect of the law of nations other than a treaty; if the case concerns the retroactive application of a constitutional provision or a previous decision of the Court; if the case concerns an exclusionary rule, the harmless error rule (though not the statute), the abstention doctrine, comity, res judicata, or collateral estoppel; or if the case concerns a "rule" or "doctrine" that is not specified as related to or connected with a constitutional or statutory provision. Consider "Supreme Court supervision of lower federal or state courts or original jurisdiction" otherwise (i.e., the residual code); for issues pertaining to non-statutorily based Judicial Power topics; for cases arising under the Court's original jurisdiction; in cases in which the Court denied or dismissed the petition for review or where the decision of a lower court is affirmed by a tie vote; or in workers' compensation litigation involving statutory interpretation and, in addition, a discussion of jury determination and/or the sufficiency of the evidence.

Opinion:
TAYLOR et al v. McKEITHEN, GOVERNOR OF LOUISIANA, et al.
No. 71-784.
Decided June 12, 1972
Per Curiam.
The 1970 self-reapportionment of the. Louisiana Legislature was challenged in this lawsuit on the dual grounds that it offended both the one-man, one-vote principle and the prohibition against voting arrangements designed to dilute the voting strength of racial minorities. After the United States Attorney General interposed an objection to. the election law change under § 5 of the Voting Rights Act of 1965, 79 Stat. 439, 42 U. S. C. § 1973c, the District Court appointed a Special Master to prepare a court-imposed plan. The Master was verbally instructed to hold hearings and to devise a proposal to maintain the integrity of political subdivisions and to observe natural or historical boundaries “as nearly as possible.” He was also instructed, that “[n]o consideration whatsoever was to be given to the location of the residence of either incumbents in'office or of. announced or prospective candidates.” Opinion of Judge West, Civil Action No. 71-234,. Aug. 24, 1971.
The Special Master held four days of hearings, during which over 100 persons were heard. Proposed plans were received by him. No one was denied a hearing. He then submitted his recommendation to the District Court and after a hearing it was adopted by the court.
This dispute involves only four state senate' seats affected by the reapportionment. At the hearing held by the District Judge on the Master’s proposal, the State Attorney General presented a counterplan which differed from the 'Master’s only with respect to four senatorial districts in the New Orleans area. Although the judge found that both plans satisfied the one-man, one-vote requirement, he found that the two schemes differed in their racial composition of the four districts, as is set out in greater detail in the margin. Under the State Attorney General’s scheme, four “safe” white districts were proposed whereas the Master’s design would have created two districts of slight majorities of black voters. Also, under the counterplan each incumbent would continue to reside in his “own” district, whereas under the Master’s proposal the residences of the four incuinbents would fall evenly between the two districts to bé composed primarily of white voters, ensuring defeat for two of the four incumbents.
At the hearing the State Attorney General contended that the court’s plan would make hash of the traditional ward-and-precinct lines. The District Court acknowledged that there would be some departure from the historical patterns but concluded that the “ ‘historical’ boundaries of voting districts in Louisiana reflect [ed]. a history of racial discrimination. Adherence to the historical boundaries alluded to by objectors [had] been the prime reason why only two negroes [had] been allowed to sit in the Louisiana Legislature in the last 75 years.” 333 F. Supp.. 452, 462. The court found that the alternative proposal would “operate to diversify the negro voting population throughout the four districts and thus significantly dilute their vote” and would practically eliminate “the possibility of a negro being elected from any of the four districts,” while the court-approved plan would at least give blacks “a fair chance in two out of the four districts. . . \” Id., at 457. The court-approved plan sought “to protect the rights of the people while the primary purpose of the Senators’ plan appear[ed] to be the protection of incumbent office holders.” Id., at. 458. Accordingly, as mentioned, the District Court adopted- the Master’s recommendation.
Despite the District Court’s findings, however, the Court of Appeals reversed without opinion and adopted the Attorney General’s alternative division of New Orleans. The petitioners are the original plaintiffs and they now seek review of this summary reversal.
An examination. of the record in this case suggests that the Court of Appeals may have believed that benign districting by federal judges is itself unconstitutional gerrymandering even where (a) it is employed to overcome the residual effects of past state dilution of Negro voting strength and (b) the only alternative is to leave intact the traditional “safe” white districts. If that were in fact the reasoning of the lower court, then this petition would present an important federal question of the extent to which the broad equitable powers of a federal court, Swarm v. Charlotte-Mecklenburg Board of Education, 402 U. S. 1, 15, are limited by the colorblind concept of Gomillion v. Lightfoot, 364 U. S. 339, and Wright v. Rockefeller, 376 U. S. 52, 57, 67 (Douglas, J., dissenting). In reapportionment . cases, as Justice Stewart has observed, “the federal courts are often going to be faced with hard remedial problems” in minimizing friction between their remedies and legitimate state policies. Sixty-Seventh Minnesota State Senate v. Beens, 406 U. S. 187, 204 (dissenting opinion).
Because this record does not fully inform us of the precise nature of the litigation and because we have not had the benefit of the insight of the Court of Appeals, we grant the petition for writ of certiorari, vacate the judgment below, and remand the case to the Court of Appeals for proceedings in conformity with this opinion.
Mr. Justice Blackmun concurs in the Court’s, judgment.
According to the District Judge’s opinion, the percentages of black registered voters in each of the four districts under each of the competing plans would be:
Master’s Attorney General’s
Plan Plan-
District 2. 51% 37.6%
District 3.'. 1,8% .25.7%
District 4. 58% 44.3%
District .5. 20% 24.0%
It is possible, but unlikely, that the Court of Appeals believed that benign districting, although permissible, was achievable here with less violence to the parish’s historical district lines. But had that been its view presumably the. court would have remanded' for the construction of a less drastic alternative rather than simply directing the adoption of the Attorney General’s counterplan.
Although similar in some respects, this case is not controlled by Whitcomb v. Chavis, 403 U. S. 124. To be sure, in both cases the District Courts were writing on clean’ slates in .the sense that they were fashioning court-imposed reapportionment plans. And, in each case the equitable remedy of the court conflicted with a state policy. (There the state policy favored multi-member districts whereas here the policy favors maintenance of traditional boundaries.) The important difference, however, is that ini Whitcomb it was conceded that the State’s preference for multi-member districts was not rooted in racial discrimination, 403 U. S., at 149. Here, however, there has been no such concession and, indeed, the District Court found a long “history” of bias and franchise dilution in the State’s traditional drawing of district lines. Cf. id., at 155.
We, of course, agree that the courts of appeals should have wide latitude in their decisions of whether or how to write opinions.- That is especially true with respect to summary affirmances. See Rule 21, Court of Appeals for the Fifth Circuit. But here the lower court summarily reversed without any opinion' on a point that had been considered at length by the District- Judge. Under the special circumstances of this case, we are loath to impute to the Court of Appeals reasoning that would raise a substantial federal question when it is plausible that its actual ground of decision was of more limited importance.

Question: What is the basis of the Supreme Court's decision?

Choices:
judicial review (national level)
judicial review (state level)
Supreme Court supervision of lower federal or state courts or original jurisdiction
statutory construction
interpretation of administrative regulation or rule, or executive order
diversity jurisdiction
federal common law

Answer: 2