What can we infer from the extraordinary decision by the attorney general to block the disclosure of letters written by Prince Charles to ministers, ordered last month by an information tribunal? They could have an impact on his ability to perform his role as the country's next king, so we are told – what does that say about the prince's judgment? The letters must be so revealing that Dominic Grieve would rather take a massive amount of flak, and put the government in an untenable position, than allow the public to know exactly how the prince tries to influence ministers.

What is the point of the Freedom of Information Act, and all the bodies set up to make sure it works, if this unelected individual is allowed to hide not just his lobbying of elected politicians but the language he uses to do it? Grieve admitted yesterday in the House of Commons that the letters contain the prince's "particularly frank" and "most deeply held personal views and beliefs". We have an idea what those might include: the prince has reactionary views on architecture, is keen on homeopathy and has often displayed a woeful incomprehension of science. But I'm now wondering what else he has sounded off on in 27 letters to seven government departments.

Since the letters cover only a seven-month period in 2004 and 2005 – which shows how long the Guardian has been trying to have them published – I'm wondering how many more of the prince's wacky opinions are nestling in files and drawers all over Whitehall. The fact that even a tiny fraction of this correspondence is deemed too controversial to be released speaks volumes about the problems this busybody royal has created for ministers.

Grieve's other admissions to the house are just as astonishing. He conceded that the prince's letters contain remarks about public affairs which "would potentially have undermined [Charles's] position of political neutrality". He also stressed the importance of the monarch being able to "engage in confidence with the government of the day, whatever its political colour". If we can't be shown the letters, it's reasonable to assume that they're not politically neutral. That means Charles has failed in one of the first requirements of a constitutional monarch before he's even ascended the throne.

It's now clear that the prince has potentially embarrassing political opinions which he has been rash enough to express in his regular attempts to wield political influence. His advisers know what his political bias is, so do ministers in a series of governments and judges who sit on the information tribunal, but the people who aren't allowed to know are the very ones that this vain and foolish man intends to rule. There are other important questions about what is being hidden. Has Charles lobbied for specific changes in government policy? If so, was he successful? Has any minister dared to tell him, very politely, to take a running jump?

Imagine this man were running for public office. Imagine he wanted to be an elected head of state, and refused to reveal a long history of using his influence secretly to influence government decisions. The outcry among rival politicians and in the media would be deafening. The very act of opposing disclosure would put an end to his aspirations, which is exactly what should happen in this case. But we, the public, have no recourse. We have no choice about this man becoming head of state and we're treated like children, not allowed to know about hugely significant matters which clearly disqualify him from performing the role. How can this be, in a democracy?

It's an iron rule of politics that the cover-up is always worse than the original act that someone desperately wants to hide. The government now finds itself in the curious position of catastrophically undermining the prince while trying to protect him. I can only assume that his views are even weirder and more indefensible than I originally suspected.