Secret correspondence between the Government and Buckingham Palace concerning the growing public cost of the Royal Family is to be released to The Independent after three years of campaigning.
In a far-reaching ruling, the Government must disclose more than 100 letters and memos written by ministers and members of the Royal Household during negotiations over public subsidies paid to the Queen for the upkeep of her palaces.
The Information Commissioner's decision deals a severe blow to the Royal Family's efforts to ensure correspondence between the Palace and the Government is not caught by the public's right-to-know law. Royal aides warned ministers that they did not want the letters disclosed to The Independent.
But the Deputy Commissioner, Graham Smith, said the public interest in releasing the letters and other documents outweighed the Royal Family's right to protection under the Freedom of Information Act. He said: "[The Commissioner] believes that disclosure of the requested information would enhance public awareness and understanding of the funding and accommodation arrangements of the Royal Household and this would be in the public interest."
The Government had also argued against disclosure because it claimed that publishing the documents would inhibit the free and frank exchange of views between ministers and so prejudice the conduct of public affairs.
But again the Commissioner said the exemption was overruled by the public interest and that disclosure would "increase transparency and accountability" in the awarding of grants to the Royal Household.
He said that by withholding the information, the Department for Culture, Media and Sport (DCMS) had breached the terms of the Freedom of Information legislation, which Labour introduced in 2000. The Government has been given 35 days to surrender the correspondence to The Independent.
MPs and republican groups have criticised the lack of transparency over the public money given to the royals, who have spent £41.5m in 2009; £1.5m more than last year.
The documents will shed light on the extent of the financial crisis at the Palace as the Queen tries to balance her books. A small number of the letters concern an application for a public subsidy for energy-saving measures, as well as money spent on security lighting and cameras. But the contents of the vast majority of the correspondence will not be known until it is handed over to The Independent.
Some of the information held contains "free and frank commentary" on the decisions being taken by the DCMS. And the Commissioner said that while he recognised that this correspondence was of a "candid" nature, it was in the public interest to understand how public money was spent and how the Government had responded to requests for funding from the Royal Household.
Palace officials admit they are still locked in a battle with Whitehall after the DCMS rejected a request for extra funds to repair the crumbling royal palaces, leaving the Queen in despair at her "patch and mend monarchy". The backlog in essential maintenance is estimated at £40m, but staff have been given just £15m for the year.
The Queen is also negotiating with the Government over an increase in the Civil List. But MPs and taxpayers' groups want a greater say in how the Royal Family is subsidised after a string of scandals over public money being spent on minor roles.
This year it emerged that £250,000 had been spent on redecorating Princess Beatrice's university accommodation. The cash helped redecorate a private four-bed apartment at St James's Palace for her use while she is a student. Last year Prince and Princess Michael of Kent were made to pay rent of £120,000 a year to stay in their Kensington Palace apartment, after almost seven years of paying only a nominal fee. Buckingham Palace has said that the royal couple will be charged the full commercial rate from 2010 to remain in their five-bedroom, five-reception home.
The move followed demands by MPs on the Commons public accounts committee that full rent should be paid for the property after it emerged that the prince and princess were paying a nominal amount.
Under a financial memorandum drawn up between the Government and the monarch, there is an obligation on the Royal Household to provide officials with easy access to any documents which have a bearing on the public cost of the accommodation of the Queen. It is this correspondence which the Information Commissioner says should be disclosed in the public interest.
In his ruling in favour of the The Independent, the Commissioner disagreed with ministers' contention that if the information was made public it would have a "chilling effect" on the future disclosure of private documents to the Government.
The Deputy Commissioner concluded: "The content of the information is such that it does not relate to the personal privacy of any member of the Royal Family, but rather the discussions relate to the spending of the Grant in Aid which is specifically in relation to the maintenance and upkeep of the Royal Household. In the Commissioner's view, disclosure would not undermine the privacy of nor the constitutional position of the Royal Family."
Yet the Palace contends: "It is particularly worth recognising that information that interests the public may not be the same as that which would be disclosed in the public interest. It is a fundamental constitutional principle that communications between the Queen and her ministers and other public bodies should remain confidential, and that the political neutrality of the Queen and the Royal Family, and the Royal Household acting on their behalf, should be maintained."
A spokesman for the DCMS said that Government lawyers were considering the implications of the ruling and would respond in due course.