Australia is witnessing a political stitch-up of extraordinary proportions. Not by Professor Gillian Triggs and the Human Rights Commission, as the Prime Minister might wail and cry. No, it is clear what is going on. The Abbott government is cynically moving to de-legitimise certain institutions that perform vital roles in the democratic life of this nation.

Its attack on the president of the Human Rights Commission is designed to enfeeble the statutory institution that is vested with the important task of observing and critiquing how Australian governments and institutions abide by the international laws of human rights, laws that this nation proudly helped to formulate and which we demand other countries uphold.

It has been a brutal exhibition of Machiavellian manoeuvrings – by the Prime Minister from the floor of Parliament, by the sleazy antics of the Attorney-General in trying to force Professor Triggs' resignation, and through the brazenly partisan conduct of Coalition senators on the legal and constitutional affairs committee. But this government's morally bankrupt and desperately misguided effort to manipulate public opinion against the commission will prove to be an own-goal.

The unpopular Abbott government is apparently so threatened by the findings of a report into children in immigration detention – a report that delivers strong criticism of both the Coalition and its Labor predecessors – that it seeks to render impotent an independent, vocal monitor. It seeks to sow doubt about the commission's credibility, so it strikes at the top.

The government says it has lost confidence in Professor Triggs. It claims she demonstrated political bias by initiating an inquiry into children in detention only after the Coalition came to power in late 2013. It argues the commission should have been concerned about children being locked up under the Rudd and Gillard governments, when numbers in detention soared. Attorney-General George Brandis embellishes this by saying Professor Triggs committed a "catastrophic error of judgment". He says there was "a near-universal view" within the Coalition by Christmas that her position had become untenable, mainly because of what he called her "inconsistent and evasive" responses before the Senate committee in November.