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Supreme Court Determines Military Needs Outweigh Possible Environmental Harm And Clarifies Preliminary Injunction Standard

By: Robert D. Thornton

In a 5-4 decision issued Tuesday, November 12, 2008, the U.S. Supreme Court vacated a preliminary injunction concerning the impact of U.S. Navy training activities on marine mammals. The Supreme Court decision has broad implications because it rejected the injunction standard utilized by the Ninth Circuit Court of Appeals in environmental cases. The Supreme Court concluded that a "possibility of irreparable injury" is not sufficient to warrant an injunction and that the plaintiffs are required to demonstrate a likelihood of irreparable injury. The Court indicated that national security interests and the opinions of military experts deserve an extraordinary amount of deference by the courts. This ruling will make it more difficult for environmental groups and others to obtain preliminary injunctions in the future.

Procedural Background

The Navy has conducted integrated training exercises off the coast of Southern California, or SOCAL, using mid-frequency active ("MFA") sonar for forty years. Antisubmarine warfare is one of the Navy's highest priorities. Modern diesel-electric submarines, which are extremely difficult to detect and track, are a significant threat to the Navy's fleet. The most effective tool to identify a submerged diesel-electric submarine is MFA sonar, and the Navy's training exercises in SOCAL are essential to operators' successful use of this technology.

The waters off the coast of Southern California are home to "at least 37 species of marine mammals, including dolphins, whales, and sea lions." (Slip Op. at pp. 3-4.) The plaintiffs alleged that there was evidence that marine mammals suffer harm from the Navy's use of MFA sonar, including hearing loss, decompression sickness, and other disruptions. The Navy, however, argued that despite forty years of naval exercises, no injured marine mammal had been found. In February, 2007, the Navy concluded that the MFA sonar training exercises would not have a significant impact on the environment and, therefore, did not require preparation of an environmental impact statement under the National Environmental Policy Act ("NEPA"). Subsequently, the Council on Environmental Quality authorized the Navy to implement alternative arrangements to NEPA compliance under provisions of the NEPA regulations governing "emergency circumstances."

The Winter plaintiffs, a coalition of environmental groups and activists, filed a lawsuit under NEPA and other environmental statutes seeking declaratory and injunctive relief.

The Ninth Circuit Decision

The litigation made several rounds through the District Court, the Ninth Circuit, and the Executive Branch before it ended up in the Supreme Court. Ultimately, however, the Ninth Circuit upheld the issuance of a preliminary injunction by the District Court.

The Ninth Circuit stated that since the plaintiffs had demonstrated a strong likelihood of success on the merits and "had carried their burden of establishing a ‘possibility' of irreparable injury" to marine mammals, the injunction should issue. Yet, it simultaneously approved the District Court's ruling that the plaintiffs had established a "near certainty" of irreparable harm. (Slip Op. at p. 12.) In addition, the Ninth Circuit held that the balance of hardships and consideration of the public interest weighted in favor of the plaintiffs, and did not defer to Naval witness declarations emphasizing the need for these exercises and the impact that the lack of effective training courses would have on national security.

The District Court's injunction allowed the Navy to use MFA sonar only as long as it implemented six specific mitigation measures. Two of those measures included "shutting down MFA sonar when a marine mammal is spotted within 2,200 yards of a vessel," (the "Shutdown Requirement") and "powering down MFA sonar" by a certain degree during "significant surface ducting conditions, in which sound travels further than it otherwise would due to temperature differences in adjacent layers of water" (the "Power Down Requirement"). (Slip Op. at p. 7.)

The Supreme Court Decision

The Navy challenged both the Shutdown and Power Down Requirements, together with Ninth Circuit's rationale upholding the injunction. The Supreme Court agreed. Writing for the 5-4 majority (part of which was joined by Justices Breyer and Souter), Justice Roberts rejected the preliminary injunction standard utilized by the Ninth Circuit and explained: "Issuing a preliminary injunction based only on a possibility of irreparable harm is inconsistent with our characterization of injunctive relief as an extraordinary remedy that may only be awarded upon a clear showing that the plaintiff is entitled to such relief." (Slip Op. at p. 12.) But the Court also concluded that even if the Ninth Circuit had articulated the correct standard for a preliminary injunction, the public interest weighed in favor of the plaintiffs and the finding that the plaintiffs had shown a "near certainty" of irreparable harm was incorrect. The Court concluded that the courts below failed to evaluate accurately the irreparable harm in light of several factors, including the fact that the Navy had been conducting the exercises at issue for 40 years, and the record contained only speculative evidence concerning harm to the marine mammals at issue. But most importantly, the Court determined that even if there was irreparable harm, the balance of equities strongly favored the Navy. Training with MFA Sonar is "mission critical" to the Navy's defense and success in detecting submarines; and it is a "highly perishable" skill for which operators need continual training. In short, use of the MFA Sonar is essential to the national defense and security. These interests outweighed the possible ecological, scientific, and recreational interests that plaintiffs represented. And although there was some degree of speculation as to the harm to Naval operations, courts are generally required to give deference to military judgment.

Take Away – A Preliminary Injunction Will Be Harder To Get

The Winter decision makes it clear that environmental plaintiffs (and others) will have a tougher time obtaining preliminary injunctions, and that substantial deference will be given to military and other expert governmental determinations.

Robert Thornton has practiced environmental law for over twenty-eight years. He represents landowners, resource developers, and public agencies on a variety of environmental matters and is nationally recognized as an expert on the Endangered Species Act and regional habitat conservation plans. He can be reached at 949.833.7800 or

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