## Facts

- The Brotherhood of Locomotive Engineers (BLE) picketed Atlantic Coast Line Railroad Company’s (ACL) Moncrief Yard near Jacksonville, Florida, in connection with BLE’s labor dispute with the Florida East Coast Railway.
- ACL sought a federal injunction to stop the picketing; the federal district court denied relief, citing limits on federal labor injunctions.
- ACL then obtained a Florida state-court injunction barring the picketing at Moncrief Yard.
- After the Supreme Court recognized federally protected picketing rights in a related railroad labor context, BLE moved in Florida court to dissolve the Moncrief Yard injunction; the state court denied the motion.
- BLE did not pursue state appellate review and instead returned to federal court seeking an injunction preventing ACL from enforcing the Florida injunction.
- The federal district court enjoined enforcement of the state-court injunction, and the Fifth Circuit affirmed.

## Issues

1. Whether the Anti-Injunction Act, 28 U.S.C. § 2283, permitted a federal court to enjoin enforcement of a state-court injunction restricting picketing.
2. Whether any § 2283 exception applied: (a) “expressly authorized by Act of Congress,” (b) “necessary in aid of” federal jurisdiction, or (c) “to protect or effectuate” the federal court’s judgments.

## Decision

- The Supreme Court reversed.
- The federal injunction against enforcement of the Florida state-court injunction violated 28 U.S.C. § 2283.
- None of the statute’s three exceptions applied.
- The “protect or effectuate judgments” exception did not apply because the earlier federal order denying an injunction did not adjudicate that federal law barred state injunctive relief, and the later federal action functioned as attempted federal review of the state court’s decision.
- The “necessary in aid of jurisdiction” exception did not apply because state and federal courts had concurrent jurisdiction and the state proceedings did not impair the federal court’s ability to act within its own jurisdiction.
- No federal statute “expressly authorized” the requested injunction against the state proceeding.

## Legal Principles

- Federal courts may not enjoin state-court proceedings unless the injunction falls squarely within one of the three exceptions in 28 U.S.C. § 2283.
- The § 2283 exceptions are narrowly construed; federal courts cannot use them to provide de facto appellate review of state-court rulings, even when federal rights are asserted.
- The “to protect or effectuate its judgments” exception applies only to prevent relitigation of matters actually decided by the federal court; it does not authorize a federal injunction where the earlier federal decision did not resolve the issue the state court later addressed.
- The “necessary in aid of its jurisdiction” exception generally does not apply where state and federal courts have concurrent jurisdiction and parallel litigation does not threaten the federal court’s jurisdiction.
- Federal labor statutes and general federal labor-law protections do not, without clear statutory language, constitute an “express authorization” to enjoin state-court proceedings.

## Conclusion

The Court held that a federal court could not enjoin enforcement of a state-court injunction limiting union picketing because the Anti-Injunction Act barred such federal interference and none of § 2283’s narrow exceptions permitted it.


Atlantic Coast Line R.R. Co. v. Bhd. of Locomotive Eng’rs, 398 U.S. 281 (1970)