One issue worth examining, but in danger of being overlooked, is the continuing role of the public service as a guardian of fundamental constitutional values, including government integrity and the rule of law. Australians rely on their governments, at all levels, to behave honestly and fairly. We expect our requests for services to be dealt with in accordance with stated rules and procedures without any favouritism or bias. We also assume that the public service will apply a legal and ethical brake on politicians, preventing them from making illegal or improper requests of their bureaucratic subordinates.

On the whole, these expectations are well-founded. Instances of public service corruption are generally isolated rather than the norm. Public concern over political corruption, as indicated by the growing support for a federal anti-corruption agency, has been directed more towards the political class than the bureaucracy. Australia is mercifully free from the systemic corruption that pervades many other countries, where citizens must be prepared to pay a bribe to secure access to routine government services to which they are legally entitled. Our public servants can generally be depended on to resist inducements or pressure from powerful interests seeking to gain an illegitimate advantage. Politicians, too, know that improper requests will be politely resisted and will generally harm their reputations.

So one can understand why the review should take ethical values for granted. The terms of reference do refer to the need for an "apolitical" and "professional" service providing "fair and equitable support where it is most needed". But the main emphasis is elsewhere, on the impact of new technology, on driving economic productivity as well as protecting security. The APS must be "fit for purpose for the coming decades, able to guide and accelerate future reform activities". The key will be greater innovation, collaboration and more skilful use of technology and data. Public service values can look after themselves.

This complacency, however, may be misplaced. Several long-term global trends pose challenges to the continuing entrenchment of APS values. First is the steadily increasing influence of private-sector assumptions and values on public-sector behaviour. The managerial reform movement, which began in the 1980s and is still running, drew inspiration from business management practices that stress efficiency and effectiveness over equity and probity. Admittedly, the Jeremiahs who prophesied at the time that managerialism would undermine the public service ethos proved alarmist, so far at least. The generation of senior public servants who led the reforms were people of unquestioned probity and the senior ranks of the APS remain ethically robust. But the APS may have relied too much on the values of earlier generations of public servants and not have done enough to imbue new cohorts with the uniqueness of public service values.

Amid all the talk of innovation, agility, efficiency and so on, which are also watchwords in the commercial world, it is easy to forget that public servants face unique ethical demands. An obvious point of contrast is in the obligation to follow due process in matters such as letting of contracts and making appointments, where private sector companies are not bound by the same ethical codes. Merit appointment is the founding principle of the APS, through its roots in the reformed British civil service of the 19th century. The fact that public servants owe their own jobs to a fair and transparent process helps to reinforce their commitment to due process when dealing with others, for example in managing contracts.

The centrality of the merit principle to APS culture, if not under threat, is certainly being played down. For instance, the latest formulation of the APS values in the 2009 revision of the Public Service Act removed merit from its position as one of the core public service values and relegated it to a separate subsection of "employment practices". More recently, in 2016, the Public Service Commission sponsored a report on the merit principle by leading businesswoman Sandra McPhee. McPhee advanced the fallacious argument that because some private sector companies use merit as a principle there can be nothing distinctive about merit as applied in the public sector. However, the use of merit in the private sector is a matter of managerial choice. In the public sector, it is an ethical and legal imperative, whether managers want it or not.

Pressure on the merit principle also comes from the growing use of consultants to perform what were previously considered core public service functions. Public servants increasingly find themselves working alongside colleagues who are employed under contract by private firms and might not be fully bound by the public service code of conduct. While such arrangements may provide advantages of reduced costs and greater flexibility, they give rise to ethical risks. We hear more reports of nepotism and cronyism on the fringes of government contracts, particularly with subcontractors. Arrangements whereby public servants resign to be immediately reappointed as consultants often give off a whiff of corruption. Over time, ministers may come to be more comfortable with employees who are more morally flexible than the traditional public servant. Public servants themselves may come to question why they are bound by stricter rules than their private-sector colleagues.

A related trend is the increasing polarisation of partisan political debate between conservatives and progressives, which is infecting political discourse worldwide. In Australia, the public service has been co-opted into these ideological wars on the side of the progressives. Since John Howard's "night of long knives" in 1996 and Kevin Rudd's ostentatious confirmation of all incumbent secretaries in 2007, the rallying point for this contest has been around political appointments to the senior ranks of the APS. The progressives and the Labor Party have claimed the moral high ground, criticising the Coalition's politicisation of the public service and supporting continuing post-election tenure for all secretaries. The Coalition, on the other hand, has insisted on its right to remove incumbent secretaries, particularly those whose loyalty might appear suspect, and to replace them with more congenial appointees.

The overall effect on the APS leadership's impartiality should not be exaggerated. For the most part, Coalition prime ministers have drawn new secretaries from within the senior ranks of the APS without affecting the service's general impartiality and its claim to be "apolitical". But there have been notable exceptions, notably the appointment of John Lloyd, from the Institute of Public Affairs, to the statutory position of public service commissioner. Many of the Coalition's conservatives clearly see the APS as a source of progressive opposition to their values, alongside other publicly funded institutions such as universities and the ABC. This perception is reinforced by the Labor-aligned Community and Public Sector Union, which assumes the role of main public defender of the APS, and by other left-wing organisations, such as The Australia Institute, which are vigorous champions of the APS. In response, right-wing culture warriors feel duty-bound to fight back, by supporting the purging of APS senior ranks from time to time and by trying to impose an ideological counterbalance.

To sustain its character as an "apolitical" public service into the future, the APS needs to be seen as truly impartial between the two sides of politics. The more it becomes a pawn in the increasingly strident battle between right and left, the harder that balancing act becomes. It may be time to reconsider the appointment process of secretaries, safeguarding the right of prime ministers to choose people they can work with but reinforcing the assumption that professionally capable secretaries must be able to work for governments of any political complexion.

A final trend that threatens the values of an independent public service is more tenuous but may prove more powerful. It involves a subtle but profound change in our wider intellectual context. Today's public servants have spent most of their professional lives assuming that the type of constitutional system in which they operate – liberal, democratic and under the rule of law – is the global paradigm of good government. Many countries may fall short of this model, but it is the form of government, as set out, for example, in the United Nations Declaration of Human Rights, to which all nations supposedly aspire and towards which they are all supposedly progressing. For Australians, and members of other similar countries, this has been a very comfortable assumption, reassuring them that their constitutional values are universally valued and envied. Though at the other side of the world from most developed democracies, Australia (along with New Zealand) has seen itself as a regional mentor and a beacon for others to follow.

This confidence is now being shaken. A rival authoritarian paradigm is challenging the liberal democratic consensus. Within our region, Australia faces a rising China, whose government shows little interest in the rule of law or public service integrity. China's influence is already being felt in universities and the media, where principles of free speech and unfettered opinion are being compromised for fear of offending the Chinese government and its close associates. Politicians are tempering their words and actions to avoid angering the new would-be hegemon.

It is only a matter of time before these pressures start to impinge seriously on public service integrity if they have not done so already. Will public servants have the courage to stand up to unlawful requests from politicians seeking to bend the rules in favour of Chinese interests and their local business supporters? In the clash between authoritarian and democratic values and the defence of Australian constitutional independence, the APS is in the frontline. Is it ready to stand firm on our account?

Such fears may be exaggerated and unduly alarmist. But, in considering whether the APS is "fit for service", issues of public service integrity should not be taken for granted.

Richard Mulgan is an emeritus professor at the ANU's Crawford school of public policy. richard.mulgan@anu.edu.au