The Human Rights Commission of Australia has been told the government should not be allowed to pick and choose what detention facilities can be scrutinised under a UN anti-torture treaty.
The Human Rights Law Centre has made a submission saying that the independent commission should decide what places of detention are inspected.
The Australian government ratified the Optional Protocol to the Convention against Torture in December, but it has denied its obligations extend to offshore facilities on Manus Island and Nauru.
The centre's Ruth Barson said it was cynical of the government to commit to the treaty, yet keep its deepest, darkest places of misery hidden from scrutiny.
She said half-baked implementation of the treaty risks undermining it.
The Human Rights Commission is holding consultations and advising the government on implementation.
The Law Centre's submission suggests the offshore facilities should be included and subject to independent inspection.