What is pivotal throughout these letters is that the Queen, through her private secretary, engages with Kerr on these inherently political matters, even advising him on the powers of the Senate and, critically, the existence and potential use of the contentious and contested reserve powers to dismiss the government.
Let’s take just one example, from the first glimpse at the letters, Charteris’ letter to Kerr of November 4, 1975, on the reserve powers: "Those powers do exist … but to use them is a heavy responsibility … I think you are playing the 'Vice-Regal' hand with skill and wisdom. Your interest in the situation has been demonstrated, and so has your impartiality. The fact that you have the powers is recognised, but it is also clear that you will only use them in the last resort and then only for constitutional and not for political reasons."
Charteris followed this up the next day with the clearest suggestion that the reserve powers may need to be used which, Charteris wrote, "places you in what is, perhaps, an unenviable, but is certainly a very honourable position. If you do, as you will, what the constitution dictates, you cannot possible [sic] do the Monarchy any avoidable harm. The chances are you will do it good". He ends with a reference to the "discretion left to a governor-general". These critical letters provided Kerr with the advice and comfort he needed to feel secure that the Palace accepted the existence and potential use of the reserve powers as he moved towards dismissing the Whitlam government.
Coming from his boss, "these powers exist, but its up to you to use them" is another way of saying "you should use them". It sounds like Australia needs another dismissal: of its interfering foreign monarch.