Lucyface,

You really need to look at the international maritime law rather than the broad brush charter. Maritime law generally prohibits the interference with vessels in international waters with the clear exception of where there is substantial indication that the boat intends to enter a nations waters to commit a crime, the nation to which the boat is headed is legally entitled to intercept the boat and take appropriate action.

Secondly as the boat problem was entirely manufactured by Labor, and the boats are entirely Indonesian, to blame the Liberals takes a outrageous liar.

".....with the clear exception of where there is substantial indication that the boat intends to enter a nations waters to commit a crime, the nation to which the boat is headed is legally entitled to intercept the boat and take appropriate action."

Shallow Minister, if you back this up with incontrovertible fact I will concede.

Highlight what specific circumstances give Australia the right to interdict on the high seas, and, where it is specified that travelling towards asylum is committing a crime under either the UN Charter, or, The Law of The Sea.

It is not illegal to turn/tow boats back once they are in Australian waters, but if asylum is claimed we have obligations.

Why should it be a secret as to how our navy behaves, both inside or outside our waters? Is it because we are doing something immoral and illegal?

Shadow Minister,
Yes, and international maritime law decrees what Greenpeace has done to the Russian Oil platform or whatever it was in the North Sea as piracy and they should be locked up for a minimum of twenty years.

Lucyface,

There are thousands of pages of documents on maritime law, often contradictory, but there is strong precedent for interdiction on the high seas, and this is regularly done by Israel, the US, and some EU countries, especially where human trafficking is concerned.

https://openaccess.leidenuniv.nl/bitstream/handle/1887/16699/06.pdf?sequence=10

This is just a small portion of a larger publication dealing with human trafficking. From the challenges posed by the phenomenon of undocumented sea migration consensus has emerged that, similar to activities as piracy, unauthorized broadcasting, the slave trade and drug trafficking, international law should broaden the basis for states to assert criminal jurisdiction over the offence of migrant smuggling, also when committed at sea. Studies suggest that, not least
due to the sharpening of maritime controls and surveillance, migrants increasingly make use of the services of smugglers in their efforts to cross the seas to Europe.86 The Protocol against the Smuggling of Migrants by Land, Sea and Air, adopted in Palermo in 2000, obliges states to criminalize migrant smuggling, defines the term ‘migrant smuggling’ and provides specific rules on the interdiction of migrant smugglers at sea.87 The Protocol is annexed to the UN Convention against Transnational Organize Crime (UNTOC),88 which expressly permits state Parties to establish (prescriptive) jurisdiction over
offences listed in the Convention which are inter alia committed outside their territory, if they are committed ‘with a view to the commission of a serious crime within its territory’.89

Even without this, the asylum seekers have to reach Australia's territorial waters (12 Nm) before asylum can be claimed. Australia has the full right to interdict and turn around boats in the contiguous zone which is 24Nm from the coast and tow them back to the edge of Indonesian waters, and some rights to do so in the economic zone which extends up to 200km off shore.

This was done successfully by Howard without breaching any legal conventions, nor the sovereignty of Indonesia.

Here is another interpretation, one I can agree with as it does not claim legally untested precedent as a basis for current activity.
http://www.abc.net.au/news/2013-09-26/government-turn-back-boat-policy/4979898