It’s a rocky time for everyone clinging to the border protection liferaft. We’ve got unaccompanied child refugees in Nauru being bashed and threatened with death and, if that’s insufficiently disturbing, coming down the pipeline is new migration and maritime legislation that enshrines the most fevered attempt to shred the rule of law.

First to Nauru, where last week Guardian Australia reported four unaccompanied boys between 15 and 17, who had refugee status and were living in the community, had been roughed-up by a group of local men on motorbikes. They made it clear that these “motherfucker refugees” were not welcome on the charmless rocky outcrop.

Two of the lads were hospitalised and all of them traumatised. Scott Morrison, characteristically, managed to be both ruthless and inaccurate. He took no responsibility for these refugees. “This incident is wholly a matter for Nauru,” he said.

It would be near-impossible to record each and every occasion Morrison dissembled, misled or was downright inaccurate. But this particular pork pie cannot be allowed to pass without taking a big bite from it. It is not entirely a matter for Nauru at all, it is mainly a matter for Morrison, for a number of reasons.

The minister may not be aware of it, but there is a well developed body of law governing state responsibility, which says nations cannot simply divest themselves of legal obligations.

The fact that Morrison is not capable of “delegating out” can be found not only in international law, but in the memorandum of understanding between Nauru and Australia. Among other things it says, “participants [ie the two countries] will treat refugees with dignity and respect and in accordance with relevant human rights standards”.

The use of the word “participants” means that this is not just on Nauru’s shoulders. Further, nothing in the document limits Australia’s human rights obligations.

Most asylum seekers sent by the Australian government to the tiny island, who are found to be refugees, are only given Nauruan visas for five years. What happens after that is unknown. Maybe a few will be sent, against their will, to Cambodia.

Settlement in Nauru was only ever a temporary “solution”. The future of these refugees is still in the hands of the Australian Department of Immigration and Border Protection.

Madeline Gleeson, a research associate at the Andrew and Renata Kaldor Centre for International Refugee Law at the University of NSW, says that until a durable solution is found, the children who have been injured and threatened are still within Australia’s obligation of care.

Nor can Morrison shrug off Australia’s international obligations under the treaties to which it is a party – specifically in this case the conventions dealing with the rights of the child, the status of refugees, and civil and political rights. In any case, the parliamentary joint committee on human rights has found the new laws breach Australia’s obligations under international law.

As recently as June this year in the case where the high court found that capping protection visas was invalid, Robert French, the chief justice, said that the Migration Act must be construed consistently with Australia’s treaty obligations - unless parliament specifically and unambiguously says otherwise.

For good measure, the European court of justice has ruled that unaccompanied children cannot be arbitrarily transferred between countries in such a way as to prolong the processing of refugee claims.

The European court of human rights, in 2012, found that countries cannot contract out of their state responsibilities. In that case, Italy could not under a bilateral agreement transfer irregular arrivals by sea to Libya.

This body of jurisprudence resonates with the prevailing Australian circumstances. But what can be done about it?

The treaties themselves do not provide remedies. Madeline Gleeson says their purpose is to establish a “normative minimum standard” for the treatment of all people within Australia’s jurisdiction, including children and refugees.

To get a remedy for youngsters in harm’s way in Nauru would require someone to get the government to court, on the basis that Morrison has breached his duty of care.

While the minister’s hand-washing routine continues, he has other treats in his locker - the daddy of them all being a bill to give him far-reaching powers over the detention and dispatch of asylum seekers, along with measures to dismantle previous high court findings and head off future ones.

The Migration and Maritime Powers Legislation Amendment (Resolving the Asylum Legacy Caseload) Bill is quite a mouthful and seeks to bite off more than the government can legally digest.

The legislation, if passed, would give power to the minister to detain people on the high seas and send them anywhere, including back to where they face persecution - in breach of the refugee convention and the convention against torture.

The convention relating to the status of refugees also comes in for a frontal attack, as the legislation removes references to it from the Migration Act. In some peculiar drafting mindset there’s a mistaken belief that once shredded from domestic law the internationally ordained obligations to refugees can be forgotten.

Other main provisions include the usual cat-and-mouse game with lawyers - empowering bureaucratic arbitrariness and limiting the rule of law. There are also provisions that would overturn the high court’s decision in June, by permitting the minister to cap the number of protection visas.

Submissions to the senate legal and constitutional affairs legislation committee are now closed, with a reporting date of November 27.

The Coalition continues to dress-up these punitive measures with the conceit that they have the humanitarian purpose of saving lives at sea - never mind the painstaking destruction of lives on land. This is the moral vacuum into which Morrison and his colleagues have plunged us.