The public service is a soft target, especially for Coalition governments, and Scott Morrison has already had it in his sights.

His early messaging has been that the bureaucracy needs to improve delivery and implementation. He’s also telling it, with a degree of bluntness, to remember the old adage – that it is on tap and the government is on top, and not to go getting too many ideas of its own.

And there will be more to come. On Monday week, Morrison will set out in detail his thoughts on the service in an address to the Institute of Public Administration. Meanwhile a review of the bureaucracy, set up by Malcolm Turnbull and chaired by business figure David Thodey, is about to land. This inquiry was charged with producing “an ambitious transformation program” to ensure the service is “fit-for-purpose for the coming decades”.

The Australian Financial Review reported this week Morrison had told the Thodey review “to take a tougher line on the performance standards demanded from the nation’s 150,000 bureaucrats”. (Whether achieving better “performance standards” in Morrison’s mind includes fixing up the present arbitrary system for chasing welfare recipients over income reporting is another matter.)

Morrison is moving his one-time chief of staff Phil Gaetjens from Treasury head to become secretary of the Prime Minister’s department; Gaetjens is replaced in Treasury by Steven Kennedy, the widely respected secretary of the Infrastructure department. Apart from a new Infrastructure secretary, other changes are expected at the top.

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Morrison’s attitudes towards the public service derive from his keen eye on voters’ needs and opinions, and the sort of leader he is.

Given his constant deriding of the “Canberra bubble”, it follows he would perceive mileage in some muscling up to what can be portrayed as a “bubble” cohort (though many of them are actually located elsewhere). Morrison understands the public want efficient delivery – and also knows putting bureaucrats in their place plays well with the shock jocks and their constituency.

As one bureaucrat puts it, Morrison is “an outcomes-oriented person. He likes doing stuff – and he likes people to work out how to do stuff in a timely way”. So, for example, he is suspicious of long processes of consultations by the public service.

Morrison’s belief that the public service shouldn’t get above itself – by having its own policy views, rather than just views on how to implement the government’s policy – hasn’t just been articulated since becoming PM.

He put the same line to Paul Tilley, former senior Treasury officer whose book Changing Fortunes: a History of the Australian Treasury, was published this week.

Tilley quotes Morrison, treasurer at the time, saying:

Treasury shouldn’t tell the Treasurer what to do. They should tell the Treasurer what they think of what the Treasurer plans to do, of alternative ways in which he can do what he wants to do … Treasury needs to remember its job is to advise the government on the government’s agenda – not to decide the agenda.

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Of course at one level Morrison is correct – it is not the bureaucracy’s job to “decide” a government’s agenda. But his argument lacks subtlety, and plays down important aspects of the advisory role that a top grade public service should have.

Tilley charts the waxing and waning of Treasury’s influence over the decades. “Through the golden years of macroeconomic and budget management of the 1950s and first half of the 1960s, then again through the nation-changing economic reforms of the 1980s and 1990s, Treasury was influential. …

"From the late 1960s to the early 1980s, Treasury still had a strong economic framework but was seen as dogmatic and was pushed out into the cold. Then, in this last decade, the balance of policy influence has again shifted away from the department”.

While timeframes and individual departmental stories will vary, it is clear that in recent years the public service generally has lost policy clout.

Reasons are multiple. Some are long standing but have increased over the years; others are more recent.

They include the ever-expanding role of ministers’ own staffs; the move (under the Keating government) to have secretaries on time-limited contracts; “reform fatigue” within government, bureaucracy and the community; the proliferation of outside sources of advice; the 24-hour news cycle; hyper-partisanship; increased outsourcing of work formerly done by bureaucrats; and the elevation of the doctrine of public service “responsiveness” to ministers.

The preliminary Thodey report in March was disappointingly bland, affected by the proximity of the election.

It is not particularly deep on this issue of advice. It does observe:

There are strong concerns that the APS’s underlying capacity has been weakened over time. … The risk is that Australia will find itself with an APS that, in coming years, struggles to provide successive governments with integrated advice and support – informed by a deep understanding of the needs of the Australian people – to best tackle complex problems.

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Does Morrison’s downplaying the advisory role of the public service matter? On several fronts it does.

In so many areas, the policy world is highly dynamic and rapidly changing. Unless the public servants are encouraged to explore the outer reaches of this world, a government will not have all the information and options that it should. It will lack the best policy telescope.

Morrison makes the government’s “agenda” sound like a once-and-for-all tablet. But a government in office for any length of time needs a constantly evolving and innovative agenda, to which bureaucratic thought and expertise can contribute.

Only an arrogant government – or one living on a temporary high after an unexpected election win - thinks it knows everything. It might come as a shock to some politicians, but departments on occasion educate their masters. Treasury, for instance, shaped John Howard’s thinking, which affected the way in which he sought to change the Fraser government’s policy thinking (albeit with limited success).

Morrison might reply that things have changed, because there are now many more fonts of ideas, in the private sector and think tanks. This is true and they should be tapped. But they won’t necessarily be superior to good public service thinking, and often they are harnessed to vested interests.

Relegating the advisory side of the public service’s role also diminishes the status of the service, making it harder to attract and keep the brightest talent.

Morrison would like a more porous bureaucracy – where people move in and out from the private sector. Again, there is value in encouraging such movement, but experience suggests it doesn’t work as well in practice as in theory.

Gaetjens’ new job as secretary of the Prime Minister’s department involves not just servicing Morrison and his government but also being the bureaucracy’s custodian and voice.

Part of his task should be to convince Morrison he needs strong and broad public service advice more than he currently thinks he does. Even if it’s sometimes unpalatable or outside the square.