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:
PAULUSSEN v. HERION
No. 85-88.
Argued March 5, 1986
Decided March 25, 1986
Esther L. Hornik argued the cause for appellant. With her on the brief were Angela L. Martinez and Donald J. Martin.
Joseph N. Onek argued the cause for appellee. On the brief was Neil H. Stein
Briefs of amici curiae urging reversal were filed for the Children’s Defense Fund et al. by Constance Jean Chatwood, Jane Howard-Martin, Marian Wright Edelman, James D. Weill, and Judith L. Lichtman; and for the Neighborhood Legal Services Association by Daniel L. Haller and Eileen D. Yacknin.
Per Curiam.
On February 17, 1980, appellant Barbara Paulussen filed a paternity and child support petition in a Bucks County, Pennsylvania, court on behalf of her daughter, who was then seven years old. The petition alleged that the daughter had been born out of wedlock, that appellee George Herion was her natural father, and that he had ceased making contributions to her support in April 1975. Appellee offered as a defense the time bar of the Pennsylvania statute of limitations, which at the time required that paternity actions be commenced within six years of the child’s birth or within two years of the putative father’s last voluntary support contribution or written acknowledgment of paternity. 42 Pa. Cons. Stat. Ann., § 6704(e) (Purdon 1982) (repealed). The defense was sustained against appellant’s contention that the statute violated the Equal Protection Clause of the Fourteenth Amendment to the Federal Constitution. The Superior Court affirmed, 334 Pa. Super. 585, 483 A. 2d 892 (1985), and the Supreme Court of Pennsylvania denied discretionary review. Appellant sought appeal in this Court, and, on October 15, 1985, we noted probable jurisdiction. 474 U. S. 899 (1985).
On October 30, 1985, Pennsylvania enacted 1985 Pa. Laws, Act No. 66, to be codified as 23 Pa. Cons. Stat. Ann. § 4343(b), which provides that a child born out of wedlock may commence a paternity action, at any time within 18 years of birth. Appellee now concedes that he is subject to § 4343(b) and that, upon a showing of paternity, he would be liable for child support payments from the date paternity was established. Brief for Appellee 5. He contends, however, that, even on such a showing, he would not be liable for payments dating back to the date the initial petition was filed in 1980.
Our examination of Pennsylvania law leaves us uncertain as to the legal consequences of the enactment of the new 18-year statute of limitations. If, however, Pennsylvania were to interpret § 4343(b) to require support payments dating back to the filing of the original petition, the constitutionality of the 6-year statute of limitations would be irrelevant. Because Pennsylvania should have an opportunity in the first instance to resolve this issue of state law, and because we are reluctant to address a federal constitutional question until it is clearly necessary to do so, we vacate the judgment below and remand for further consideration in light of the intervening change in state law.
It is so ordered.

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