King Charles has become Britain’s first monarch in modern times to reveal how much tax he pays on his private income: £24.6m over the past two years. This is not a victory for transparency but a win for those who wish to keep the curtain drawn firmly over the royal finances.

What is presented as a radical move is in fact more obfuscation. The monarch says he has paid millions in tax, but has not disclosed the income, gains or deductions behind the bill. The royals are funded by taking a cut of crown estate profits – public money that would otherwise go to the Treasury. That amount is decided by three royal trustees: the prime minister, the chancellor and the keeper of the privy purse.

The royals have been forced into making the smallest of concessions over their wealth because of the scandal involving the king’s brother, Andrew Mountbatten-Windsor, and the late sex offender financier Jeffrey Epstein. That saw MPs drop their self‑imposed gag on discussing constitutional monarchy – and begin an investigation into properties leased at cheap rates to the royal family.

The palace has obscured scrutiny over the royals’ public and private sources of wealth for decades. The Windsors insist their duchy income, estimated to be worth more than £1bn over the past 70 years, is “private”. The taxpayer’s contribution is also weighted in their favour. This year, the sovereign grant gives the king 12% of crown estate profits: £132m now, rising to £138m next year. From 2027-28, the rate jumps to 20.5%, supposedly because the windfall from leasing the seabed for offshore green energy will have faded. For the palace, it is: heads I win, tails I win.

There are two questions here. One is about accountability to parliament. It was the Tory prime minister David Cameron who in 2011 removed a recurring act of scrutiny by MPs and replaced it with an automatic claim on profits from a publicly owned estate. What had been a periodic parliamentary reckoning became, in Mr Cameron’s words, “a generous settlement”. Since then there has been no effective check preventing the royal household’s resources from quietly expanding. There should be one – and it should come in the form of a regular Commons debate. The crown was not the author of British democracy; it was one of the power centres that democracy had to tame.

The second question is about tax. In the 19th century Queen Victoria paid tax on her civil list cash from the Treasury, her revenues from the Duchy of Lancaster, and any private income. Her heirs negotiated a series of exemptions, which meant that by the second world war King George VI was paying almost no tax at all. Then, in 1992, the monarchy partially retreated when public anger made that position unsustainable. Queen Elizabeth II did not embrace taxation as a civic duty. It was crisis management after royal scandals, recession-era resentment and fury that the public might have to pay for repairs to Windsor Castle.

The same idea seems to be behind the latest announcement as the public fumes at the rising costs of essentials and seethes at the disgraceful behaviour of Mr Mountbatten-Windsor. The issue is not whether the monarchy pays some tax. It is whether a family sitting on vast personal wealth should enjoy substantial public funding, opaque private income and state-financed renovation works all at once.

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