Opinion of Sotomayor, J.
that defendants may raise. It permits what it calls an “undue burden” defense, but redefines that standard to be a shell of what the Constitution requires: Rather than considering the law’s cumulative effect on abortion access, see Whole Woman’s Health v. Hellerstedt, 579 U. S. 582, 609–624 (2016), it instructs state courts to focus narrowly on the effect on the parties, §§171.209(b)(2), (d)(2). It further purports to impose retroactive liability for abortion care provided while the law is enjoined if the injunction is later overturned on appeal, §171.208(e)(3), as well as for abortion care provided while Roe and Casey are in effect if this Court later overrules one of those cases, §171.209(e).
As a whole, these provisions go beyond imposing liability on the exercise of a constitutional right. If enforced, they prevent providers from seeking effective pre-enforcement relief (in both state and federal court) while simultaneously depriving them of effective post-enforcement adjudication, potentially violating procedural due process. To be sure, state courts cannot restrict constitutional rights or defenses that our precedents recognize, nor impose retroactive liability for constitutionally protected conduct. Such actions would violate a state officer’s oath to the Constitution. See U. S. Const., Art. VI, cl. 3. Unenforceable though S. B. 8 may be, however, the threat of its punitive measures creates a chilling effect that advances the State’s unconstitutional goals.
II
This Court has confronted State attempts to evade federal constitutional commands before, including schemes that forced parties to expose themselves to catastrophic liability as state-court defendants in order to assert their rights. Until today, the Court had proven equal to those challenges.
In 1908, this Court decided Ex parte Young, 209 U. S. 123. In Young, the Court considered a Minnesota law fixing
