Charles uses Human Rights Act to guard Duchy's tax secrets even though HMRC said disclosure would be in public interest

Prince Charles, pictured, has used the Human Rights Act and the Official Secrets Act to block details about his tax affairs from emerging

Prince Charles has used the Human Rights Act and the Official Secrets Act to block revelations about his tax affairs – even though Her Majesty’s Revenue and Customs has said the disclosure would be in the public interest.

The move follows a bid to uncover the secret arrangements which allow the Prince of Wales to avoid paying tax on the Duchy of Cornwall, his vast estates which generated £18 million profit last year.

The test case centres on a request by an academic who has asked to see correspondence between the Duchy of Cornwall and HMRC.

But the Government and the Duchy of Cornwall have refused to agree to the release of the documents because the disclosure would breach Charles’s right to privacy. They also say the information is protected by the Official Secrets Act.

John Kirkhope, an expert on trusts law from Weston-super-Mare, Somerset, is trying to use the Freedom of Information Act to uncover how HMRC came to grant the Duchy a tax exemption which is estimated to have been worth millions of pounds over the past century.