"The Australian people," Abetz said, "are fed up with the repeated incompetence displayed by Professor Triggs", under whose watch the commission was "masquerading as a self-appointed PC police unit". Greens spokesman Nick McKim, on the other hand, saw confirmation that Triggs would not be reappointed as "the final indignity in a sustained campaign against an eminent Australian" who was simply doing her job. Having failed to force her to resign, the government had "resorted to sacking her".

Lost in the noisy reaction was the point that Triggs herself had already indicated clearly to the government that she would not seek a second term. Turnbull's announcement was no more than confirmation of a known fact, though it offered him a handy bone to throw to the ravening attack dogs on his backbench.

The imminent end of Trigg's term as president offers a convenient opportunity to assess her handling of the role. Has she been a courageous martyr, standing up bravely for fundamental values against an immoral and unlawful government? Or has she been a self-righteous loose cannon, ignoring some freedoms while claiming to uphold others, and straying well beyond her office's permitted functions? The truth lies somewhere between the polarised extremes of partisan debate, though much nearer the honourable end of the spectrum. As a simplified characterisation, Aristotle's account of the tragic hero comes closest: a person of distinction in the community brought down by a combination of circumstances and misjudgment.

The statutory functions of the Human Rights Commission and its president are wide-ranging. They cover investigating and seeking to conciliate complaints of unlawful discrimination as well reporting to the minister on acts or practices that, in the commission's opinion, may be contrary to human rights. The commission also has a general brief to promote public understanding and acceptance of human rights and to encourage discussion of them. The breadth of its remit is underlined by a general injunction in the Human Rights Commission Act to have regard for "the individuality and universality of human rights" and "the principle that every person is free and equal in dignity and rights".

The Gillard government appointed Triggs as president in 2012, just over a year before the election of the Abbott government. Tony Abbott himself and his Attorney-General, George Brandis, already held critical views about the commission, particularly its role in investigating complaints under the vexed section 18C of the racial discrimination act. They also shared the view, common among many conservatives and libertarians, that the commission was too concerned with discrimination on grounds of race and gender and not enough with protecting civil liberties, including freedom of speech.

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Brandis moved quickly to initiate changes to section 18C. He also appointed a new commissioner, Tim Wilson, a known free-speech advocate from the Institute of Public Affairs and critic of the commission, "to restore balance" to the commission.

Triggs, it should be noted, took the rebuke on the chin, accepting the government's right to appoint commissioners and to introduce changes in the commission's governing legislation. She welcomed publicly Wilson's appointment, provided he was prepared to work cooperatively with other commission members. In the event, Wilson proved a valuable contributor to the commission until his resignation earlier this year to enter Parliament as a Liberal MP.

The breakdown of trust between the government and Triggs appears to date from the commission's report on children in detention, The Forgotten Children, which was eventually published in February 2015. It was highly critical of the conditions under which children were detained. It called for a royal commission into the practice of detaining children, which it labelled a clear breach of international law. Abbott, as prime minister, expressed immediate outrage, describing the report as "blatantly partisan". Why had the commission waited until after the Coalition government was elected before investigating the detention of children that had also flourished under Labor? Indeed, by stopping the boats, the Coalition could say it had reduced the problem by cutting the numbers of children involved.

In response, Triggs argued the report was not partisan in intent because it dealt with actions taken by both Labor and Coalition governments, which were equally culpable. However, her timing left her and her colleagues open to an imputation of political bias in targeting the Coalition's treatment of asylum seekers while going easy on Labor. This was enough to unleash the conservatives' pent-up animosity to the commission and the entire human rights agenda.

But what was the commission supposed to have done? Was it expected never to investigate the detention of children for fear of upsetting the government of the day? Surely not. Some risk of appearing partisan is implicit in many inquiries conducted by independent government watchdogs, such as the auditor-general and the ombudsman as well as the human rights commission. Governments have a right to expect that inquiries are not obviously biased or gratuitously partisan in intent. In this respect, it's notable that the commission carefully chose a subject of unquestionable moral concern (the treatment of children) and an aspect where both sides of politics were equally culpable. Governments can't demand immunity from inquiries that might appear to single them out just because they are the incumbent government of the day.

The treatment of asylum seekers placed governments on a collision course with the commission. Turning back boats and offshore detention run contrary to various international instruments, including the United Nations' refugee convention and other covenants to which Australia is a party. Though the policy is accepted by both main political parties and has wide popular support, no government has had the intellectual courage to admit the extent to which the policy departs from international norms. The commission, however, can't hide. It's legally required to report on human rights issues and to advise the minister on issues where governments appear to be in breach of international human rights. A government is free to disagree vigorously with any view the commission expresses, but it should respect the commission's right to comment from a human rights perspective.

Soon after The Forgotten Children was published, it emerged that the government had tried to remove Triggs from office. Attorney-General's Department secretary Chris Moriatis reported at Senate estimates that he met Triggs a few months earlier and told her she had lost the minister's confidence. Without explicitly asking her to resign, Moriatis offered her an alternative government position in lieu. But Triggs refused to budge and has stayed put. In spite of predictions that her position had become untenable and she would soon leave quietly, she will have seen out the remaining 2½ years of her term in full.

For a statutory officer such as the Human Rights Commission president to lose the confidence of the relevant minister is a serious matter. The commission's effectiveness depends on its president having a good working relationship with the attorney-general and the Attorney-General's Department. Apart from needing the department for administrative support, the president can't fulfil the central function of offering relevant advice to the attorney-general unless the minister has confidence in his or her judgment and is willing to listen.

Fault for the initial breakdown appears to lie with Brandis, who arrogantly used his secretary to deliver the vote of no confidence and whose general demeanour suggests someone who lacks tact or personal sensitivity. But should Triggs share some of the blame? Within the wider public service, agency heads usually accept prime responsibility for maintaining good relations between themselves and ministers, no matter how disorganised, stubborn or incompetent individual ministers may be.

Admittedly, Triggs is the head of an arm's-length statutory authority, not a standard government department, and is not subject to direct ministerial control. But the Human Rights Commission is still part of the executive branch of government with statutory obligations to advise its minister. Attorneys-general have a right to expect that the president will act as a loyal servant of the government in carrying out his or her statutory obligations. While these obligations may on occasion force the commission into open disagreement with the government, the commissioner's duty is to express such disagreement within a framework of overall respect for the government of the day and its mandate. This means avoiding unduly partisan comment or siding openly with the government's opponents.

By contrast, particularly since her run-in with Brandis, Triggs has accepted a high public profile as a wide-ranging critic of the government. Some of her reported remarks appear to cross the line between legitimate rights-based comment and political advocacy. For example, she incautiously linked the government's policy of boat turn-backs to Indonesia's lack of engagement on the death penalty issue. She criticised Parliament (i.e. the Coalition) for failing to provide leadership on marriage equality. She openly criticised politicians for losing any sense of the rule of law, a statement she initially denied making but was later forced to acknowledge.

Taken in isolation, such statements may seem excusable, even justifiable. They certainly have not merited the venomous and ill-informed attacks launched by ministers and conservative columnists in the News Limited press. On the other hand, in the aftermath of a (properly) critical report on children in detention and an open breach with the minister, perhaps it was time to keep one's head down, to avoid further public comment and to try to build bridges with the government. By allowing herself to become a lightning rod for the conservative attack on political correctness, she has helped to politicise her position in a way that may do long-term damage to the commission.

Her progressive supporters, naturally outraged by her treatment, have rallied in her defence. In doing so, many have made exaggerated claims for the level of statutory independence attached to her position. They have overlooked its status as part of the executive branch and have wrongly interpreted government attacks on the commission as tantamount to breaches of the constitutional separation of powers.

Similar claims were made on behalf of the ombudsman, when the previous incumbent, Allan Asher, was forced to resign after suggesting critical questions about detention policy for a Greens senator to ask in a committee hearing. The ombudsman, it was stated (wrongly), is an officer of Parliament, independent of the executive, with an unfettered right to criticise government actions.

Watchdog officers in the executive, such as the ombudsman, auditor-general and president of the Human Rights Commission, certainly have a degree of statutory independence. But it's limited to the effective performance of their respective statutory duties. Any broader claims to independence suggest an inflated view of their role, which may induce them into risky confrontations with ministers. It may also hamper their "guide-dog" functions of providing principled advice to governments. These functions depend on mutual trust and respect, and are undermined by open confrontation with ministers.

Where to draw the line between speaking out and keeping quiet is a matter of fine judgment that requires sensitivity to the political context. Whether Triggs has always displayed such judgment must be open to question. Certainly, in deciding how to react to government provocation, she would be unwise to listen to members of her vociferous cheer squad, however seductive their message.

Richard Mulgan is an emeritus professor at the Crawford School of Public Policy at the Australian National University. richard.mulgan@anu.edu.au