Janus v. American Federation of State, County, and Municipal Employees, Council 31, 138 S. Ct. 2448 (2018), held that the Constitution forbids public-sector unions to take "fair-share fees" from non-union members, and its holding is retroactive. Petitioner Stacey Mooney is seeking a refund of the "fair-share fees" that the Illinois Education Association diverted from her wages before Janus. The Seventh Circuit rejected her claim after holding that 42 U.S.C. § 1983 establishes a "good-faith defense" for private defendants that resembles the qualified immunity available to government officers. Pet. App. 23a–28a. Ms. Mooney's petition presents two questions:

1. In Wyatt v. Cole, 504 U.S. 158 (1992), this Court held that qualified immunity is categorically unavailable to private entities who violate 42 U.S.C. § 1983. See id. at 167 ("[Q]ualified immunity for public officials [is] not applicable to private parties."). In response to Wyatt, several courts of appeals have allowed private entities to assert a "good-faith defense" in lieu of qualified immunity when they are sued under 42 U.S.C. § 1983, which allows private defendants to escape liability if they violate another's constitutional rights before the courts have clearly established the illegality of their conduct. Other decisions from courts of appeals, however, reject the idea of a "good-faith defense" and hold private parties liable whenever they violate 42 U.S.C. § 1983—regardless of whether the violation occurred in good faith. The question presented is: Does 42 U.S.C. § 1983 provide a "good-faith defense" to private entities who violate another's constitutional rights before the courts have clearly established the illegality of their conduct?

2. Assuming that 42 U.S.C. § 1983 establishes a "good-faith defense" for private defendants, the parties disagree over its scope. The union believes that its good-faith reliance on pre-Janus statutes and court rulings should shield it not only from liability for damages, but also from restitutionary remedies that merely require the return of property that was taken in good faith but in violation of another's constitutional rights. Ms. Mooney acknowledges that defenses such as qualified immunity or "good faith" can shield a defendant from liability for damages, but these defenses never allow defendants to enrich themselves by keeping money or property that they took in violation of the Constitution. The issue presented is: Do the defenses of qualified immunity or "good faith" allow a defendant who takes another person's money or property in violation of the Constitution—but in reliance on a statute or court ruling that purported to authorize its conduct and is only later declared unconstitutional—to keep that money or property when the owner sues for its return?

Does 42 U.S.C. § 1983 provide a 'good-faith defense' to private entities who violate another's constitutional rights before the courts have clearly established the illegality of their conduct?