Anti-whaling crusader Paul Watson hopes to come to Australia early next year. But he may face arrest if he does — and he’s challenged the Australian Federal Police to leave him alone.

Watson is currently on a Sea Shepherd ship off New Zealand, heading to Antarctic waters to harass the Japanese whaling fleet. The protest mission has four ships, 120 crew and aerial drones to locate the whalers.

Watson has been a regular visitor to Australia, particularly Hobart and Perth, where he has met politicians and supporters and given speeches.

Not this time around; it seems the law has finally caught up with the professional protester. Earlier this year he was jailed in Germany on charges pressed by Costa Rica, relating to a 2002 protest against shark-finning in Guatemalan waters. Watson skipped bail and is now a fugitive; a “red notice” issued by Interpol puts him on a global wanted list.

Watson calls the Costa Rican charges “ludicrous” and motivated by Japanese politics — Sea Shepherd claims if Watson was extradited to Costa Rica he’d then be extradited to Japan to face separate charges in relation to Antarctic whaling protests. But Watson told Crikey from aboard the Steve Irwin: “I’m not too concerned about it.”

The whaling fleet has left Japan and is expected to start hunting in Antarctic waters later this month. Watson, a Canadian who carries a US passport, told Crikey he would not call into Australia on his way to join the hunt because he did not want to get arrested and tied up in court proceedings. However, he wanted to “put it to the test” with a visit after the whaling season finished early next year.

“I would hope that if they do seek to arrest me they will have a hearing in Australia to discuss how ludicrous the charge is,” he said.

Watson claimed there were 78,000 gangsters under observation in Japan, and suggested authorities arrest them instead of him.

Interpol issued a red notice on Watson some time ago — which describes him unflatteringly as being 120kg with white hair — at Japan’s request, on charges including hooliganism. Watson has entered Australia since and not been arrested. A second notice has now been issued on behalf of Costa Rica. A red notice is an alert rather than an arrest warrant, although Interpol’s website says some member countries “consider a Red Notice to be a valid request for provisional arrest”.

A spokesman for Australia’s Attorney-General’s Department said:

“Australia does not arrest a person on the basis of an Interpol Red Notice alone. Australia can only effect the arrest of a person in Australia wanted to face prosecution in another country if that country has sought the person’s extradition in relation to the offences alleged against the person.”

The spokesman said it was the government’s policy not to reveal if an extradition request had been lodged by a country until after an arrest had been made. It’s not known if Costa Rica has made such a request (although they did with Germany).

“The issue,” according to Australian National University international law professor Don Rothwell, “then becomes whether Costa Rica has issued an international arrest warrant for Watson that Australia is required to act upon, and whether Costa Rica is an ‘extradition country’ for the purposes of the Extradition Act.”

Rothwell notes Australia appears to take red notices seriously. Daniel Snedden, aka Captain Dragan, was subject to an Interpol red notice issued by Croatia relating to war crimes; he was arrested in NSW in 2010 and the government has approved his extradition to Croatia.

Rothwell also raises the possibility Australia could interdict a Sea Shepherd vessel at sea (in Australia’s “territorial sea”, for example near Macquarie Island) and arrest Watson.

Former Greens leader Bob Brown, who has been involved with Sea Shepherd visits in the past, said it would be “extraordinary” if Watson was arrested in Australia.

“He has enormous public support in this country,” Brown told Crikey. “The Japanese whaling fleet is breaking international law, and Paul Watson is upholding international law. Curiously enough, they’re punishing the upholder of the law in Paul Watson.”

Brown said the legal processes which followed on from any arrest should be carried out in Australia, not in Costa Rica.

There is also the issue of whether Watson would be granted a visa to enter Australia, which includes a character test. Any warrant would show up on the Immigration Department’s systems and may scotch a visa. But Rothwell says seafarers like Watson don’t need a visa, unless they stay over a certain period of time.

A spokesman for the Japanese embassy in Canberra told Crikey:

“If Japan receives information on the location of Paul Watson, Japan will consult with the relevant local authorities before seeking extradition. And upon such consultation, Japan will co-ordinate with the appropriate authorities of the country in which Paul Watson is located for his extradition.”