Winter, Secretary of the NAVY v. Natural Resources Defense Council, Inc.

Seat of court
Washington D.C.
Date of opinion

The US Navy was using mid-frequency active (MFA) sonar during its training exercises off the coast of southern California. The plaintiffs argued that the use of sonar causes serious injuries to marine mammals and sued the Navy, asking for declaratory and injunctive relief on the basis that the Navy had violated NEPA by conducting harmful sonar training without having first prepared an Environmental Impact Statement (EIS). The District Court granted the injunction after determining that the plaintiffs had shown a probability of success on their NEPA and CZMA claims. The court of appeals upheld the injunction because the negative impact of the injunction on the Navy was considered speculative, and because the balance of hardships and the public interest favored the plaintiffs. The Navy filed a petition for a writ of certiorari with the U.S. Supreme Court. The Court rules that the standard for granting an injunction used by the lower court (requiring only a possibility of irreparable harm) was too lenient. But even if the plaintiffs could have shown that there was a likelihood of irreparable harm (the correct standard), this was outweighed by the public and Navy’s interest in effective and realistic training. Deference must be given to the military with regard to the relative importance of a particular military interest.

Language of document
Reference number
555 U.S. 7
The preliminary injunction is vacated to the extent challenged by the Navy. The balance of equities and the public interest tip strongly in favor of the Navy. The Navy's need to conduct realistic training with active sonar to respond to the threat posed by enemy submarines plainly outweighs the interests advanced by the plaintiffs.
Court cases cited
Munaf v. Green, 553 U.S. 674 (2008)
Los Angeles v. Lyons, 461 U.S. 95 (1983)
Mazurek v. Armstrong, 520 U.S. 968 (1997)
Legislation cited
The National Environmental Procedure Act, 42 U.S.C. § 4321 et seq.
the Coastal Zone Management Act, 16 U.S.C. § 1451 et seq.
the Endangered Species Ac, 16 U.S.C. § 1531 et seq
the Marine Mammal Protection Act, 16 U.S.C. § 1361 et seq.