...many of the most sensitive papers from Britain's late colonial era were not hidden away, but simply destroyed. These papers give the instructions for systematic destruction issued in 1961 after Iain Macleod, secretary of state for the colonies, directed that post-independence governments should not get any material that "might embarrass Her Majesty's government", that could "embarrass members of the police, military forces, public servants or others eg police informers", that might compromise intelligence sources, or that might "be used unethically by ministers in the successor government".

...documents show that colonial officials were instructed to separate those papers to be left in place after independence – usually known as "Legacy files" – from those that were to be selected for destruction or removal to the UK. In many colonies, these were described as watch files, and stamped with a red letter W.

...Painstaking measures were taken to prevent post-independence governments from learning that the watch files had ever existed. One instruction states: "The legacy files must leave no reference to watch material. Indeed, the very existence of the watch series, though it may be guessed at, should never be revealed."

...Many of the watch files ended up at Hanslope Park. They came from 37 different former colonies, and filled 200 metres of shelving. But it is becoming clear that much of the most damning material was probably destroyed. Officials in some colonies, such as Kenya, were told that there should be a presumption in favour of disposal of documents rather than removal to the UK – "emphasis is placed upon destruction" – and that no trace of either the documents or their incineration should remain. When documents were burned, "the waste should be reduced to ash and the ashes broken up".

In June 1957, Eric Griffiths-Jones, the attorney general of the British administration in Kenya, wrote to the governor, Sir Evelyn Baring, detailing the way the regime of abuse at the colony's detention camps was being subtly altered.

From now on, Griffiths-Jones wrote, for the abuse to remain legal, Mau Mau suspects must be beaten mainly on their upper body, "vulnerable parts of the body should not be struck, particularly the spleen, liver or kidneys", and it was important that "those who administer violence … should remain collected, balanced and dispassionate".

Almost as an after-thought, the attorney general reminded the governor of the need for complete secrecy. "If we are going to sin," he wrote, "we must sin quietly."

Interview with Meir Dagan, former chief of the Mossad

Lesley Stahl: You have said publicly that bombing Iran now is the stupidest idea you’ve ever heard. That’s a direct quote.

Dagan: An attack on Iran before you are exploring all other approaches is not the right way how to do it... The regime in Iran is a very rational regime.

Stahl: Do you think Ahmadinejad is rational?

Dagan: The answer is yes. Not exactly our rationale, but I think that he is rational.

Stahl: Do you think they’re rational enough that they are capable of backing down from this?

Dagan: No doubt that the Iranian regime is maybe not exactly rational based on what I call Western-thinking, but no doubt they are considering all the implications of their actions.

Dagan says the best solution is to push the mullahs out by supporting Iranian students and minorities. According to a leaked State Department cable, he told his American counterparts as early as 2007, more should be done to foment regime change.

Dagan: It’s our duty to help anyone who likes to present an open opposition against their regime in Iran.

Stahl: Has Israel done anything to encourage, help, support the youth opposition groups that have been marching against the regime?

Dagan: Let’s ignore the question.

Dagan: We are going to ignite, at least from my point of view, a regional war. And wars, you know how they start. You never know how you are ending it.

- Spire Healthcare, the UK's second largest private healthcare company, is channelling £65m a year through a Luxembourg subsidiary of Cinven, its private equity owner, almost wiping out its taxable UK earnings.

- Care UK, which operates NHS treatment centres, walk-in centres and mental health services across England, is reducing its tax liability by routing £8m a year in interest payments on loan notes issued in the Channel Islands.

- Circle Health, the self-styled “social enterprise” that became the first private company to take over the management of an NHS hospital, is owned by companies and investment funds registered in the British Virgin Islands, Jersey and the Cayman Islands.

- Ramsay Health Care, the company with the greatest number of healthcare provision contracts in the NHS, has used a subsidiary in the Cayman Islands to finance the purchase of a French health company for its Australian parent company.

- General Healthcare Group, the biggest private hospital group in the UK, has registered the ownership of its hospitals through subsidiaries in the British Virgin Islands, potentially avoiding stamp duty when its owners come to sell. Its corporate structure may also mean its owners will not pay UK capital gains tax.

Gains and losses 2007 - 2009 (US)