A US appeals court has labeled militant conservationist group Sea Shepherd as pirates, and cleared the way for Japanese whalers to pursue legal action against them.
"You don't need a peg leg or an eye patch" to be a pirate, declared chief judge Alex Kozinski of the Ninth Circuit US Court of Appeals, overturning a lower court's ruling against Japanese whalers, who he said were "researchers."
"When you ram ships, hurl glass containers of acid, drag metal-reinforced ropes in the water to damage propellers and rudders, launch smoke bombs and flares with hooks; and point high-powered lasers at other ships, you are, without a doubt, a pirate," he said.
This was true "no matter how high-minded you believe your purpose to be," he added in a ruling that dubbed Sea Shepherd founder Paul Watson "eccentric."
Sea Shepherd is chasing the Japanese fleet hunting whales off Antarctica, as it has done for years in a bid to prevent the mammals being slaughtered.
Japan's Institute of Cetacean Research and others are pursuing legal action in the United States, seeking an injunction against their activities on the high seas.
In its ruling Monday, the Ninth Circuit court overturned a US district judge's ruling and allowed the Institute of Cetacean Research to pursue their action against the anti-whaling group.
The plaintiffs "are Japanese researchers who hunt whales in the Southern Ocean," which is regulated by an international convention, of which the United States and Japan are signatories, it noted.
The convention "authorizes whale hunting when conducted in compliance with a research permit issued by a signatory," said the ruling.
"Cetacean has such a permit from Japan. Nonetheless, it has been hounded on the high seas for years by a group calling itself Sea Shepherd Conservation Society and its eccentric founder, Paul Watson."
It concluded: "The activities that Cetacean alleges Sea Shepherd has engaged in are clear instances of violent acts for private ends, the very embodiment of piracy. The district court erred in dismissing Cetacean's piracy claims."
The appeals court also ruled the case should be transferred to another district judge.
"The district judge's numerous, serious and obvious errors identified in our opinion raise doubts as to whether he will be perceived as impartial in presiding over this high-profile case.
"The appearance of justice would be served if the case were transferred to another district judge, drawn at random, and we so order in accordance with the standing orders of the Western District of Washington," it said.
Japan claims it conducts vital scientific research using a loophole in an international whaling ban agreed at the International Whaling Commission (IWC), but makes no secret that the mammals ultimately end up on dinner plates.
Japan defends whaling as a tradition and accuses Western critics of disrespecting its culture. Norway and Iceland are the only nations that hunt whales in open defiance of a 1986 IWC moratorium on commercial whaling.