The plaintiffs-appellants (Institute of Cetacean Research / Cetacean) are Japanese researchers who hunt whales in the Southern Ocean. The United States, Japan, and many other nations are signatories to the International Convention for the Regulation of Whaling 1946, which authorises whale hunting when conducted in compliance with a research permit issued by a signatory State. Cetacean has such a permit from Japan. Nonetheless, it has been hounded on the high seas for years by a group called the Sea Shepherd Conservation Society and its founder, Paul Watson (Sea Shepherd). Cetacean commenced an action against Sea Shepherd, seeking a preliminary injunction. Cetacean argued that Sea Shepherd’s acts qualified as piracy and violated the Convention for the Suppression of Unlawful Acts against the Safety of Maritime Navigation 1988 (SUA Convention 1988).

Held: Sea Shepherd’s acts qualified as piracy. Preliminary injunction granted.

The United Nations Convention on the Law of the Sea 1982 (UNCLOS) defines 'piracy' as 'illegal acts of violence or detention, or any act of depredation, committed for private ends by the crew or the passengers of a private ship ... and directed ... on the high seas, against another ship ... or against persons or property on board such ship'. The Court explained that 'private ends' included those pursued on personal, moral or philosophical grounds, such as Sea Shepherd’s professed environmental goals. Although Sea Shepherd believed itself to be serving the public good, it did not render its acts being in the public good. Therefore, the Court found that the activities that Sea Shepherd engaged in were clear instances of violent acts for private ends, the very embodiment of piracy.

A plaintiff seeking a preliminary injunction must establish that it is likely to succeed on the merits. The SUA Convention 1988 prohibits acts that endanger, or attempt to endanger, the safe navigation of a ship. This only requires that Sea Shepherd creates dangerous conditions, regardless of whether harmful consequences ensue. Cetacean presented uncontradicted evidence that Sea Shepherd's acts could seriously impair its ability to navigate. The Court found that Sea Shepherd at least attempted to endanger the navigation of Cetacean's ship and Cetacean was likely to succeed on the merits of the claim with respect to the SUA Convention 1988. Therefore, the Court granted the preliminary injunction.