Accusing Russia of "violating human rights," Dutch representatives appeared before the International Tribunal for the Law of the Sea (ITLOS) Wednesday to ask that the court demand the release of the Greenpeace Arctic 30.
Russia, whose coastguard detained the 30 activists following their September protest on a Russian Arctic drilling platform, declined to attend the hearing.
"The argument of the Netherlands is that in international waters, ships have the right to freedom of navigation and so this means they may not be boarded, inspected, detained or arrested except with the permission of the flag state," Greenpeace international general counsel Jasper Teulings told Reuters.
Russia is currently holding the protesters on the charge of hooliganism, which carries up to seven years in jail. This sentence was reduced from the initial charge of piracy, though supporters of the Arctic 30 deem both charges excessive for what was deemed a peaceful protest.
According to reports of the hearing, Dutch government representative Liesbeth Lijnzaad said Russia had "violated the human rights" detaining them for seven weeks "without grounds."
As the "flag state" of the Greenpeace ship Arctic Sunrise, which carried the protesters, the Netherlands is taking the legal steps necessary to gain release of the ship and the Arctic 30.
In a statement released Wednesday, Greenpeace International said they were "confident that the Tribunal will take appropriate account of the fundamental rights of the Arctic 30, and the impact of their detention on those rights, in reaching its eventual decision."
The Dutch hope the tribunal will rule by mid-November, securing the provisional release of the 30 activists.
The ITLOS is an independent judicial body established to resolve maritime disputes, particularly the interpretation and application of the United Nations Convention on the Law of the Sea (UNCLOS), of which both the Netherlands and Russia are signatories.
Of the Russian Federation's decision to abstain from the hearing, Greenpeace said that although they are not "formally obliged to participate in the hearing," they are, however, "under an obligation to comply with any ruling which the Tribunal may make."
Also Wednesday, UK Prime Minister David Cameron released a statement calling for "prompt, fair and proportionate action" by the Russian judicial system.