Paradise Papers: Prince Charles's estate, the Duchy of Cornwall, invested through Caribbean tax havens
Prince Charles, pictured with Camilla the Duchess of Cornwall, had "no direct involvement" with investment decisions. (AAP Image/Tracey Nearmy)
The British Royal family's use of offshore tax havens has been exposed in the Paradise Papers, with the latest revelation showing Prince Charles's estate investing through a friend into a forestry company in Bermuda.
Earlier this week it was revealed the Queen's personal estate had committed more than 10 million pounds ($17 million) through tax havens, with some of her money ending up invested in a UK hire purchase company accused of predatory lending.
The Royals' use of tax havens has been questioned by a spokesman for Tax Justice Network Australia, Mark Zirnsak.
There is no suggestion of wrongdoing in the investments made by the Queen or Prince Charles, who voluntarily pay tax on the income from their estates.
But Dr Zirnsak said legitimate uses of tax havens could come at a high cost to reputations given illegal and unethical uses of offshore tax shelters that include tax evasion, fraud, money laundering and concealing assets.
"It will have sullied her reputation, definitely … even if everything is above board, it just does not look good," Dr Zirnsak said.
"It would have been much better to put your money somewhere where it's been managed and invested with a reputable firm, where it's all transparent and you're very clear what you're willing to invest and what you're not.
"To get yourself connected in these tax havens and these secrecy arrangements is not a good look."
Dr Zirnsak said secrecy was sometimes a motive behind well-known people investing through tax havens.
The revelations have exposed more information than was previously available about the Royal family's investments through their private estates, and revealed for the first time their use of funds in offshore tax havens.
Company kept Prince's identity secret
In the latest revelation, leaked documents show Prince Charles's personal estate invested in a company in Bermuda called Sustainable Forestry Management that is associated with one of his oldest friends, Hugh van Cutsem.
The documents show the Prince's personal estate, the Duchy of Cornwall, was introduced to the fund by Mr van Cutsem, an old Cambridge University friend of the Prince.
Mr van Cutsem died in 2013.
The company also agreed to keep the Prince's investment of about $130,000 secret.
A February 2007 board minute noted: "The Chairman thanked Mr van Cutsem for his introduction of the Duchy of Cornwall and asked and the Board unanimously agreed that the subscription by the Duchy of Cornwall be kept confidential except in respect of any disclosure required by law."
By 2008, the Prince's estate had sold the shares for about $425,000.
Mr van Cutsem was an officer and shareholder in the company, which appears to have been set up to profit from increased trade in emission offsets by buying forests and other land across the globe, attracting high-profile investors.
But its plans came to grief in the global financial crisis, and it was eventually liquidated in 2011.
The Duchy of Cornwall's other investments shown in the Paradise Papers, a leak of 13.4 million documents examined by Four Corners in partnership with the International Consortium of Investigative Journalists, include two limited partnership private equity funds headquartered in the Cayman Islands.
Duchy of Cornwall established in 1337
The Duchy of Cornwall is Prince Charles's private estate, first established in 1337 by King Edward III for his son Prince Edward.
The Prince is entitled to the annual income from the estate's assets of about $1.5 billion.
The estate recorded income of about $34 million in 2016-17, on which the Prince voluntarily pays income tax.
The Duchy of Cornwall told the ICIJ's partner The Guardian that its accounts "are independently audited and presented to parliament every year".
"The Prince of Wales does not have any direct involvement in the investment decisions taken by the Duchy. These are the responsibility of the Duchy's finance and audit committee," it said.
The revelations are contained in documents from global offshore law firm Appleby.
Those documents, and documents from Singaporean trust firm Asiaciti and 19 registries in international tax havens, were originally obtained by German newspaper Suddeutsche Zeitung, becoming the largest leak of documents in history.
Queen's estate linked to 'predatory' firm
Earlier this week it was revealed Queen Elizabeth II's private estate, the Duchy of Lancaster, invested $13 million in a Cayman Islands fund.
The documents also revealed the Queen had previously invested in a fund headquartered in Bermuda.
The Queen's estate has invested millions of pounds in Caribbean firms. (AP: Carl Court)
Further investigations by the Guardian revealed the Cayman Islands fund used by the Queen's estate had in turn invested in a private equity company that controlled BrightHouse, a UK hire purchase firm.
The firm has been accused of predatory lending, charging customers interest rates as high as 99.9 per cent.
Last month it was ordered to repay almost $25 million to nearly 250,000 customers after failing to meet its responsible lending obligations.
A spokeswoman for the Duchy of Lancaster said the Duchy's investment decisions were not made by the Queen.
"We are not aware of any tax advantages to the Duchy in investing in offshore funds," she said.
"The Duchy's investment policy is based on advice and recommendations from our investment consultants and asset allocation rather than tax strategy."