FEDERAL Police have again raided Sea Shepherd ships despite repeated failures to find legal grounds to pursue the anti-whaling group at Japan's request.
For the fourth year in a row, the police yesterday began an investigation into Sea Shepherd, following the Southern Ocean clashes with the Japanese whaling fleet over the summer.
This came despite advice there was insufficient evidence to prosecute in the only investigation yet finalised, and admissions by the Department of Foreign Affairs and Trade that it has exhausted legal avenues to ban the ships.
The Greens leader, Bob Brown, said officials were being pressured by the Japanese government to act against Sea Shepherd, and he urged the Foreign Affairs Minister, Kevin Rudd, to lodge a complaint with Tokyo.
Sea Shepherd's flagship, Steve Irwin, and the group's long-range vessel, Bob Barker, docked in Hobart after forcing the whaling fleet to withdraw from the Antarctic halfway through its season having taken less than one-fifth of its quota.
''I'm actually quite convinced, about 75 per cent certain, that they won't be back again,'' the group's leader, Paul Watson said. ''But if they are we will be ready to go back.''
He said in each of the past seven Antarctic campaigns, Sea Shepherd's operations grew stronger, while the heavily subsidised whaling fleet's capacity declined under the weight of financial pressures from Tokyo.
The fisheries agency of Japan regards the prospect of returning to the Antarctic as ''extremely gloomy'', according to the national newspaper, Yomiuri Shimbun. However, no public statement of permanent withdrawal has been made by the Japanese government.
Declassified government documents obtained under freedom-of-information laws by Senator Brown show that Australia has repeatedly acted against the group at Japan's request under the Convention for the Suppression of Unlawful Acts Against Safety of Maritime Navigation.
The police confirmed it had received referrals to investigate incidents in the past four seasons.
Its 2007-08 investigation focused on clashes between the Steve Irwin and whale chaser Yushin Maru No. 2. ''These matters were finalised on September 21, 2009, following advice from the Commonwealth Director of Public Prosecutions that there was insufficient evidence to commence a prosecution,'' a police spokeswoman said.
She said investigations into seasons 2008-09 and 2009-10 were continuing.
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