Democracy's hidden wiring

He continued tellingly but contentiously: "I do not think that the Governor-General can require such an assurance or make the appointment conditional on such an assurance."

On the contrary, Her Excellency had an obligation to ensure that the House's position was actively respected.

Though not spelt out in detail in law, it is assumed that a prime minister either has the confidence of the House or, where appropriate, is on the way to a general election. For the House to give its confidence, either explicitly or, as in the present case, implicitly, it must know in a formal sense – not just from what its members may learn from the media – who the prime minister is.

Her Excellency's instincts, as far as we know them, were thus well-placed and show that she certainly understood what has been called the hidden wiring which underlies the functioning of the Constitution.

Her Excellency's insight was acute. She sought only that the House be informed of what had transpired so that it had the opportunity to act if and as it so wished.

Her approach was fully in accord with Paul Hasluck's treatment of the vice-regal role. He stressed not simply observance of the Constitution and the laws of the Commonwealth but also "the customary usages of Australian government."

The same cannot be said for Dr Orr (nor, according to his letter, the Solicitor-General). Dr Orr's minimalist reading seems to look upon a prime minister's commission as some sort of contract with the Governor-General, and a very limited one at that.

It might be good law but the statecraft is decidedly deficient. Fortunately, in a formal sense, Mr Rudd resolved the matter in an undated memorandum to Her Excellency received at 8.07 am on 27 June.

In seeking a commission, he stated: "Should you commission me, it is my intention to announce this to the House of Representatives at the nearest opportunity. The House is due to convene at 12pm today and I would make such an announcement at this time."

This course of events constitutes a precedent for future commissions of prime ministers so it would be valuable, indeed, obligatory, that the Acting Solicitor-General, or even the Solicitor-General himself, amplify the advice of 26 June. Brevity in state papers is much to be admired but a five-sentence letter is really not sufficient.

There remains the matter of the Solicitor-General's role as apparently sole adviser to the governor-general in cases of this sort (save for the departing prime minister). While not inconsistent with the Law Officers Act, it does not follow that a solicitor-general will necessarily have the range of expertise or experience needed; so it seems to have turned out on 26 June 2013.

In the United Kingdom, the principal private secretaries to the Queen and the prime minister, the Cabinet Secretary, and possibly also the Clerk of the House of Commons would come into play. As adjudged necessary they would seek advice on such legal questions as may arise.