Beveridge & Diamond

U.S. Supreme Court Vacates Injunction Against Navy’s Use of Sonar

Beveridge & Diamond, P.C. - NEPA Alert, November 13, 2008

The United States Supreme Court once again has reiterated that courts may not issue broad injunctions based on the unsubstantiated possibility of environmental harm.  The Court vacated two contested aspects of a preliminary injunction against the United States Navy that restricted sonar use during training exercises because plaintiffs failed to demonstrate the “likelihood” of irreparable injury to the environment without the injunction.  The ruling provides sound footing for parties to demonstrate the overriding public interest in continuing a challenged project or activity while agencies remedy procedural violations of the National Environmental Policy Act (“NEPA”).

In Winter v. Natural Resources Defense Council, No. 07-1239, 555 U.S. ___ (Nov. 12, 2008), the Supreme Court considered the propriety of a California federal district court’s injunction restricting the scope of a Navy sonar-training program.  Plaintiffs filed suit challenging the Navy’s environmental assessment, which concluded that using “mid-frequency active” (“MFA”) sonar in training to identify enemy submarines does not significantly affect the environment.  Plaintiffs alleged that the Navy should have prepared an environmental impact statement analyzing these effects and requested a preliminary injunction until the lawsuit was resolved.  The district court granted the injunction, finding that plaintiffs were likely to succeed on the merits of their NEPA claim, they had established the “possibility” of irreparable environmental harm from injury to marine mammals, and this injury outweighed any possible harm to the Navy from enjoining the sonar use.  The district court also did not find persuasive an interim determination by the Council on Environmental Quality that “emergency circumstances” warranted continuing the Navy exercises notwithstanding possible environmental impacts.  On appeal, the Ninth Circuit upheld the injunction. 

The Supreme Court reversed.  The Court determined, irrespective of plaintiffs’ likelihood of success of the merits, the mere “possibility” of environmental harm is insufficient to support a preliminary injunction.  Irreparable harm must be “likely” to occur if the court does not enjoin a challenged activity.  Because there was no documented evidence of injury to marine mammals during the Navy’s 40-year history of using MFA sonar, the Court found that plaintiffs failed to meet this standard. 

Even if continued sonar use likely would irreparably injure marine mammals, the Court determined that the public interest and Navy’s interest in effective military training would outweigh this injury.  In doing so, the Supreme Court reaffirmed the importance of assessing the balance of equities and the public interest when considering injunctive relief.  Here, plaintiffs’ “most serious possible injury would be harm to an unknown number of marine mammals that they study and observe”; meanwhile the Navy would be forced to deploy an inadequately trained antisubmarine force, which could jeopardize the safety of the entire fleet.  Under these conditions, the Court concluded, the balance of equities and the public interest tipped “strongly” in favor of the Navy.  The challenged restrictions in the preliminary injunction therefore were improper.

While the Court did not reach the merits of the underlying NEPA claim, the procedural issues it decided are far more important and may extend beyond the particular facts of this case.  Although the Court’s majority focused on the overriding public interest in national security, its guidance should not be limited to cases involving the military.  In reaching its conclusion, the Court confirmed that preliminary injunctions are “an extraordinary remedy never awarded as of right” and activities may not be enjoined on the basis of speculative harm.  For all cases, the lower courts must identify the likelihood of irreparable injury and appropriately balance the parties’ respective harms and interests and the public interest before framing any injunctive relief.  When performing this balancing in future non-military cases, courts will focus on the scope of a challenged activity, its likely environmental effects, and the likely public interest impacts of enjoining the activity while procedural violations of NEPA are remedied.  As a result, parties are now in a far better position to contest preliminary relief founded on claims of hypothetical environmental impacts where the activity or project at issue serves an important public interest.   

For additional information or to discuss the implications of this ruling on your project, please contact Fred Wagner,, Parker Moore,, James Auslander,, or Patrick Jacobi,

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