Here is the question presented:
This Court established in Ex parte Young, 209 U.S. 123 (1908), that a plaintiff may sue state officials for prospective injunctive relief against the enforcement of an unconstitutional state law. In the intervening years, this Court and most courts of appeals have repeatedly held that Ex parte Young allows federal courts to enjoin the future enforcement of state tax schemes that violate federal law or the Constitution. This Court has also observed that an injunction requiring a state’s future compliance with federal law does not violate state sovereign immunity, even if it has a “substantial ancillary effect on the state treasury.” Papasan v. Allain, 478 U.S. 265, 278 (1986).
In this case, however, the Eleventh Circuit concluded otherwise. It departed from this Court’s precedent, and “create[d] a circuit split,” Pet. App. 24a (Jordan, J., concurring in part and dissenting in part), when it held that Ex parte Young does not permit the Seminole Tribe of Florida to seek injunctive or declaratory relief against the future unconstitutional enforcement of Florida’s fuel tax scheme. The court’s holding turned on the fact that Florida precollects this tax from a third party, which means that an order barring future enforcement against the tribes might require the state to issue tribal consumers refunds “from state coffers,” supposedly in violation of the Eleventh Amendment. Pet. App. 12a.
The question presented is whether sovereign immunity bars an American Indian tribe from seeking Ex parte Young relief from the unconstitutional enforcement of a state tax scheme merely because that relief might require refunds for taxes unlawfully collected in the future.
Lower court materials and my commentary here.