What has pushed the monarch to breaking point, it seems, was not the infamous paparazzi shots of events such as the Duchess of York having her pedal digit sucked by her "financial adviser" John Bryan. Rather it is innocent enough shots like the one of her two grandsons wading through the river with their father's personal assistant, Miss Tiggy Legge-Bourke. The picture was taken near Loch Muick, a beauty spot on private land often visited by the family during their August holiday.
However innocuous a snap, the Queen has decided that it is too much an invasion of privacy. It is, she feels, impossible for the royals to relax even on private land while they are subject to the predations of paparazzi of increasing boldness equipped with ever more powerful telephoto lenses. Only one of the four photographers had replied to her letter by the weekend deadline.
Coming on the heels of the injunction obtained last week by the Princess of Wales to stop a motorcycle courier-turned-freelance photographer going within 300 metres of her, the move has prompted reports that the Queen's tolerance is reaching its limits. That fact has significant implications for the rumbling debate on privacy laws.
Of particular concern to the Queen is said to be the fact that her grandsons, particularly Prince William, are showing increasing reluctance to travel to Balmoral. The language of the Buckingham Palace official who came forward to make and on-the-record statement was forceful in palace terms. The Royal Family was "entitled to enjoy a few private moments and not be spied upon by a handful of photographers".
There are those who will dismiss this as royal whingeing. Those of a conspiratorial frame of mind may well place credence on the report in one of the tabloids that the clampdown is because Prince Charles has invited his former lover, Camilla Parker-Bowles, to be a guest at Balmoral next week, as soon as his decree absolute is through.
Certainly the tabloids are on the track of that one. Stuart Higgins, the editor of the Sun, admitted as much on the radio at the weekend, when he said that if he was offered a photograph of Charles kissing Camilla he would print it.
Such a brazen admission will only increase disquiet among those wary of the implications for press freedom, yet finding it difficult to defend intrusion into individual privacy.
The problem is that laws framed to outlaw a Charles-kisses-Camilla photograph would also make illegal the publication of a shot of a Cabinet minister at a private party with, say, an arms dealer he claimed never to have met. Measures to suppress publication of Prince Charles's notorious "I wish I was a tampon" mobile phone conversation would also prohibit the taping of the deal between the minister and the gun-runner.
The difficulty is deciding where to draw the line. At the extremes it is easy enough. The Queen opening Parliament is a public event. The Queen opening her Christmas presents is private. But what where the two imperatives collide - as in investigations of her wealth, to estimate whether she is paying the appropriate amount of tax?
Privacy laws here are notoriously difficult. Even last week Lord Rodgers, chairman of the Advertising Standards Authority, was agonising in the case of the Demon Blair poster whether politicians had to concede that their privacy is invaded by their consent when they enter public life. A man's credit card account is his own affair; but surely that judgement is altered when the man is Chancellor and he has been over his Access credit limit 22 times in 8 years, as Norman Lamont had.
This is an area of fine judgements. Many of those who objected to lurid accounts of David Mellor's affair with an actress none the less felt that reports of his holidays at the expense of the daughter of a Palestine Liberation Organisation official were in the public interest. A similar of judgement could be made in the case of Rupert Pennant Rea, erstwhile deputy governor of the Bank of England: his sexual liaisons in the governor's office may have been a private matter, but bypassing security arrangements to get his lover access to the bank's inner citadel was not.
Many obvious solutions evaporate with scrutiny. An investigative press is one of the checks and balances of democracy. Few would want the restrictive privacy regime of a country like France. Under its laws John Birt, the director general of the BBC, and John Sweeney of the Observer, are being sued for "criminal slander" by the reclusive businessmen, David and Frederick Barclay, on the grounds that BBC broadcasts can be picked up in Normandy. They have objected under French law to the publication of their address in Monaco, their date and place of birth and the names of their parents, wives and children. Such details may seem irrelevant. Yet it is to imply no impropriety on the part of Barclay brothers to suggest that there might be other cases in which the less scrupulous might use the names of wives, parents or children to disguise transactions which need investigation in the public interest.
The hoary distinction between the public interest and what interests the public is harder to maintain in practice than in theory. Has Liam Gallagher traded his right not to be photographed in the supermarket in return for the fame Oasis has brought him? When Martina Navratilova celebrated winning at Wimbledon by kissing and hugging another woman, could she expect no one would ask who she was?
If Julia Carling - ex-wife of the England rugby captain, Will Carling, who counted, at one time, the Princess of Wales among his close friends - gives explicit interviews about certain aspects of her private life, can she expect that other newspapers will still regard the area as off- limits? A ruling by the Press Complaints Commission decided that she could not.
Such examples make a tightly-framed privacy law difficult to realise. There are those who argue that the best option is to draw up a privacy law in general terms and then leave it to the good sense of judges to interpret which part of an individual's private life might be acceptably violated with the defence of the public interest.
Given the track record of the judiciary in upholding the suppression of information in seminal cases like Spycatcher and Thalidomide, this might produce very mixed blessings. But as technology advances, and new lenses and bugging devices become capable of capturing what is now unseen, pressure will grow. In such circumstances, continuing to alienate the monarch might not be the best strategy.