Last Sunday Shadow Attorney General the Hon Mark Dreyfus QC MP explained
"As part of its commitment to international law and institutions, Australia also contributed greatly to the development of the international law of the sea, and played a constructive and influential role during negotiations that led to the 1982 United Nations International Law of the Sea (UNCLOS). Australia ratified that Treaty when it came into force in 1994."
"In 2002, then Foreign Minister Alexander Downer, quietly withdrew Australia from the maritime jurisdiction of the International Court of Justice, and the International Tribunal on the Law of the Sea"
This withdrawal, also known as "the carve out" is what takes out the umpire, denying Timor-Leste access to third party adjudication on Maritime Boundaries in the ICJ or ITLOS.
The Joint Standing Committee on Treaties made a report on this at the time called "Two declarations by Australia" and the version we have linked has some highlights and annotations to give context.
The last few sentences are striking - considering where we are at today ...
"While a majority of Committee members agree with the conclusions stated in 4.29, 4.30 and 4.31, Mr Wilkie, Mr Evans, Mr Adams, Senator Kirk, Senator Marshall, Senator Stephens and Senator Bartlett do not.
Specifically these members believe that the ICJ declaration made by the Minister for Foreign Affairs damages Australia’s international reputation and may not be in Australia’s long-term national interests.
The declaration may be interpreted as an effort to intimidate and limit the options of neighbouring countries in relation to any future maritime border disputes.
It should also be noted that Australia has never had an adverse finding from the ICJ.