A US court's decision declaring anti-whaling group Sea Shepherd "pirates" could have potentially far-reaching implications, a University of Canterbury law expert says.
The 9th US Circuit Court of Appeals this week castigated Paul Watson and members of the Sea Shepherd Conservation Society he founded for the tactics used in their relentless campaign to disrupt the annual Japanese whale hunt in the Southern Ocean.
In his decision summary, Chief Judge Alex Kozinski said to be a pirate "you don't need a peg leg or an eye patch".
"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. No matter how high-minded you believe your purpose to be," Judge Kozinski said.
Law professor Karen Scott said characterising the activities of Sea Shepherd as piracy had potentially far-reaching implications for international law.
"I don't agree with the court's interpretation of piracy, which has the effect of substantially broadening the scope of this offence," Scott said.
"Piracy is a crime of universal jurisdiction and pirates can therefore be prosecuted by any state even where there is no connection between the prosecuting state and the pirates, pirate vessel or the victims. Moreover, any state can board and seize a pirate vessel on the high seas.
"These rights do not generally apply to other offences committed at sea. One potential consequence of this decision, particularly if it were followed in other jurisdictions, would be to permit Sea Shepherd vessels to be boarded by any state on the high seas and for its crew to be prosecuted in any jurisdiction.
"This arguably goes too far and cannot be supported under international law as it stands today."
Scott was surprised the court made no reference to legal proceedings from Australia and New Zealand in the International Court of Justice in 2010, challenging Japan's scientific whaling programme under the 1946 International Convention on the Regulation of Whaling.
"It would appear that not only is the battle in the Southern Ocean on-going but an equally undignified one is developing in the US courts over this matter," Scott said.
While an international treaty has banned commercial whaling for 25 years, certain countries, including Japan and Norway, have been issued permits top hunt whales for "scientific research".