The case of the Prince and the property developer has reached its conclusion. The development of Chelsea Barracks was shelved last year after Prince Charles put pressure on the Qatari royal family, one of the scheme's investors, over the proposed architectural design.
The High Court ruled yesterday that the Qataris had breached a contract with their UK partners when they bowed to the Prince's will. The judge also described Prince Charles's intervention as "unexpected and unwelcome".
Prince Charles is perfectly entitled to his views. Indeed, many will have sympathy with his distaste for modern architecture in general and the proposed Chelsea Barracks development in particular. But what is concerning about this incident is not aesthetics, but hidden influence. Prince Charles put pressure on the Emir of Qatar as one royal to another. And we discovered the full details of his intervention only because this court case was brought by the Qataris' disgruntled business partners.
This is part of a pattern of Prince Charles using his influence behind the scenes of public life. Over the years, many government ministers have received so-called "black spider" letters (named after the Prince's distinctive scrawl) on subjects ranging from homeopathy to agriculture.
The Prince's spokesman says that whoever receives his employer's opinion is under no obligation to follow it. That would be true if the Prince were a normal private citizen. But he is not. He is the heir to the throne. One day he will be head of state. His seal of approval will be required for all legislation. That adds up to significant influence. As Mr Justice Vos noted yesterday, faced with a personal request from the Prince, the Qataris "could not do nothing".
The essential problem with the conduct of Prince Charles is that he displays insufficient understanding of the modern function of royalty and its necessary limitations. Prince Charles needs to learn that giving public speeches on subjects that interest him is one thing and that exerting influence behind the scenes is quite another. The Prince needs, in short, to stop meddling.