Pierre v. Holder

(1) Whether the biological basis for sex discrimination articulated in Nguyen v. Immigration and Naturalization Service can be extended to unrelated facial sex and legitimacy-based distinctions in 8 U.S.C. § 1432(a), or whether such distinctions are unconstitutional, as four Justices concluded in an order for an equally divided court in Flores-Villar v. United States; and (2) whether heightened scrutiny, the ordinary standard of review for sex and legitimacy-based distinctions, applies to such distinctions in the citizenship context.