THERE’S an unsettling moment 10 minutes into the new Dispatches documentary about royal finances, when Charles and Camilla emerge from their tartan-bedecked home in Birkhall, Aberdeenshire to clap for NHS workers during the Covid pandemic.

Camilla can hardly wait to begin her applause, smiling wryly at the camera and readying her hands while Charles is still getting into position. She wears a rictus grim as she claps away like a woman possessed, eyes fixed on the camera.

In fairness, she probably wasn’t the only person who found this weekly gesture absurd and was press-ganged into doing it. But it’s the perfect set-up for one of the most startling revelations in The King, The Prince & Their Secret Millions: that King Charles’s private estate is set to earn £1.4 million over 15 years from leasing a building to an NHS trust for the storage of ambulances.

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While this is just one of many sources of public money that make up the “secret millions” of the title, the deal was not as hush-hush as many others uncovered by this joint investigation by the Sunday Times and Channel 4.

Indeed, the Duchy of Lancaster proudly trumpeted about it in January 2023, saying: “We are delighted to be able to help and support the trust’s ambition to upgrade to an all-electric fleet.”

It was certainly a delightful deal for King Charles, whose estate will rake in more than £800,000 a year from Guy’s and St Thomas’s NHS Foundation Trust. At 67% more than the sum paid by previous tenants the Metropolitan Police, this doesn’t exactly feel like “mates’ rates”.

Equally mind-boggling are the revelations about Prince William’s estate, the coffers of which are being topped up by some of the charities for which his father acts as a patron.

A building in London that has housed offices for Marie Curie and Macmillan is owned by the Duchy of Cornwall, which receives one-third of rents collected for those office spaces. That the royals are giving with one hand and taking away with another is obscured by the fact that these rents are paid to a “head tenant”, Thames Water, which sublets the building.

An awful lot is obscured when it comes to the deals that make both duchies highly profitable commercial operations, but one thing we do know for certain is that neither is subject to corporation tax or capital gains tax.

While Charles and William “voluntarily pay income tax”, we are not allowed to know how much they pay, or what they count as legitimate expenses when they voluntarily calculate their incomes.

The Duchy of Lancaster told Dispatches that “while His Majesty the King takes a close interest in the work of the Duchy, the day-to-day management of the portfolio is the responsibility of the Duchy Council and executive team”. That is very convenient, as presumably all the questionable deals can be blamed on someone else.

Prince William will surely be looking for someone to blame for the staggeringly tone-deaf statement given by the Duchy of Cornwall in response to the documentary’s revelations about the condition of its portfolio of domestic properties, cited as evidence of the environmental hypocrisy of the monarchy.

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A joint investigation by Channel 4 and the Mirror found 14% of the Duchy of Cornwall’s rented homes and 13% of the Duchy of Lancaster’s failed to meet the minimum legal energy efficiency standards for landlords, with Energy Performance Certificate ratings of F or G. Tenants spoke of living in fuel poverty and dealing with problems including recurrent mould.

It surely adds insult to injury for them to hear their landlord is planning “targeted mental health support” for tenants while working towards a goal of net zero by the end of 2032, a mere nine winters away.

Doubtless it has not occurred to William that step one in his plan to improve the mental health of his subjects should be to stop contributing to their problems. Only then would it be appropriate to focus on what might generously be called his charitable “work”.

It is very difficult for the media to access information about how the duchies operate – as evidenced by the need for multiple collaborations to produce the Dispatches film – and one wonders if William is even aware of the many and varied ways in which the private estate he recently inherited generates profit. Or does greed trump ethics?

Defenders of the monarchy often like to portray republicans as motivated by bitterness and envy, and unwilling to see the benefits the royals bring to the country as well as the vast inherited wealth from which they benefit.

But the latest revelations – that the Duchy of Cornwall is getting £37m from the Ministry of Justice for an empty prison, £1m in access charges from the Royal Navy and god knows how much to let the army train on Dartmoor – must give even the most ardent of royalists pause.

The tax-dodging of the royals was already an outrage, but now we learn they are brazenly picking our collective pockets too. How can this possibly be defended?