Whenever you hear about an incident happening at sea and you are interested in the legal consequences of that event, the most important question to ask is: where did it happen?
This is a fundamental to figuring out who is in the right and who is in the wrong when it comes to Japanese "scientific" whaling in Antarctic waters.
From the Federal Court's decision this week on the case filed by Humane Society International, it is also clear that the answer to "where did it happen" can vary depending on whether you are looking at Australian law or international law.
Under the Environment Protection and Biodiversity Conservation Act, Australia has declared a whale sanctuary in the exclusive economic zone off the Australian Antarctic Territory. The rights of a coastal state in this maritime zone are set out in the 1982 Law of the Sea Treaty, to which Australia and Japan are both parties.
According to that treaty, Australia is allowed to exercise rights over fishing activities, including marine mammals, and is granted powers to enforce its fisheries laws through the arrest and seizure of vessels.
The Act reflects these powers and it was on the basis of that legislation that Justice James Allsop was able to issue an injunction against the Japanese whaling company on Tuesday.
However, it is not evident that Australia is entitled to enforce the injunction in the economic zone claimed off Antarctica as a matter of international law. Many states, including Japan, contest Australia's right to claim an economic zone off the Australian Antarctic Territory, given that Australia does not have sovereignty over that area. These diplomatic sensitivities have meant that, as a matter of practice, Australia has not sought to enforce its laws against foreigners in its claimed zone.
As Japan doesn't recognise Australia's claim to an economic zone off Antarctica, it takes the view that the area is high seas.
A spokesman for the Institute of Cetacean Research said this week the actions of the Sea Shepherd's activists constituted an act of piracy by boarding a vessel on the high seas. As the high seas, no country has ownership over those waters and a country's authority is generally limited to vessels flying its flag.
Australia is only entitled to exercise jurisdiction over Japanese vessels on the high seas in very limited circumstances if the Japanese vessels were involved in piracy, slave-trading or unlawful broadcasting, or if Australia and Japan had both consented by treaty to boardings for enforcing drug-trafficking or fishing laws. No such treaty exists here. Even if one of these exceptions could be established, it is only the Australian Government which is permitted to undertake the boarding and not an activist group.
While the Sea Shepherd activists weren't permitted to conduct a boarding on the high seas, it doesn't necessarily mean they are "pirates". International law has long taken a severe view of pirates, branding them as the "enemies of all humankind". Whenever pirates are found on the high seas, any state is allowed to detain and arrest them.
It may be easy to get caught up in visions of Johnny Depp the moment pirates are mentioned, but as a legal matter a number of criteria need to be met for someone to be branded a pirate. Under the Law of the Sea Treaty, an act of piracy has to be committed "for private ends", which has always been understood as money, or other valuable goods. By contrast, if a vessel is boarded for the purposes of a political statement, or to make a mail delivery, then those involved are not pirates and should not be treated as if they are the enemies of all humankind.
The limited authority a state has over the high seas is why Australia's Customs vessel, the Oceanic Viking, is only planning to monitor the activities of the whaling fleet once it reaches Antarctic waters. Any aggressive action by the Oceanic Viking against the Japanese fleet is likely to fall foul of Australia's requirement to show due regard to the rights of other users on the high seas.
It is nonetheless an important voyage to make, as it not only maintains the diplomatic pressure on Japan in registering Australia's continued opposition to so-called "scientific" whaling, but may also provide evidence Australia needs in mounting a court case against Japan.
Of course, in collecting that evidence for a possible trial, it will still be important to know: where did it happen?
Dr Natalie Klein is at Macquarie University's division of law. She was on a panel of legal experts advising the International Fund for Animal Welfare on Japan's whaling under international law.