judgment. The letter instead reflected the Executive's own conclusion, relying on a definition still being debated and considered in the courts, that heightened equal protection scrutiny should apply to laws that classify on the basis of sexual orientation.
Although "the President ... instructed the Department not to defend the statute in Windsor," he also decided "that Section 3 will continue to be enforced by the Executive Branch" and that the United States had an "interest in providing Congress a full and fair opportunity to participate in the litigation of those cases." Id., at 191–193. The stated rationale for this dual-track procedure (determination of unconstitutionality coupled with ongoing enforcement) was to "recogniz[e] the judiciary as the final arbiter of the constitutional claims raised." Id., at 192.
In response to the notice from the Attorney General, the Bipartisan Legal Advisory Group (BLAG) of the House of Representatives voted to intervene in the litigation to defend the constitutionality of §3 of DOMA. The Department of Justice did not oppose limited intervention by BLAG. The District Court denied BLAG's motion to enter the suit as of right, on the rationale that the United States already was represented by the Department of Justice. The District Court, however, did grant intervention by BLAG as an interested party. See Fed. Rule Civ. Proc. 24(a)(2).
On the merits of the tax refund suit, the District Court ruled against the United States. It held that §3 of DOMA is unconstitutional and ordered the Treasury to refund the tax with interest. Both the Justice Department and BLAG filed notices of appeal, and the Solicitor General filed a petition for certiorari before judgment. Before this Court acted on the petition, the Court of Appeals for the Second Circuit affirmed the District Court's judgment. It applied heightened scrutiny to classifications based on sexual orientation, as both the Department and Windsor had
