Material artefacts such as failed technologies and traces of a collapsed building are disposed of, documents are shredded or made hard to access and media stories are drowned out with fresh online content.
See Page 16: "Dispose of documents containing the Company's confidential or proprietary information with care so as to avoid inadvertent disclosure".
The S.E.C.'s policy had long been to dispose of documents related to a preliminary investigation if the agency's enforcement division decided to close the inquiry.
He and his associates hid or disposed of documents that would shed light on his two other major professional achievements: his Olympics leadership in Utah and his administration as governor of Massachusetts.
The policy to dispose of documents was almost unknown outside the S.E.C. until last year, when Darcy Flynn, an employee for 13 years in the S.E.C.'s enforcement division, took the information to the National Archives, which began an investigation in July 2010.
A spokesman for Mr Letwin said: "Mr Letwin has signed an undertaking with the Information Commissioner's Office and will dispose of documents containing personal data in a secure manner.
According to a person close to the case, Mr. Duncan told investigators that he disposed of documents in keeping with the Oct. 12 e-mail message from an Andersen lawyer in Chicago and that the destruction stopped when the lawyer left a voice mail message at the Houston office on Nov. 9.
But on January 15th, it said that a partner whom it has now sacked called an urgent meeting to organise the effort to dispose of documents after learning that Enron had received a request for information from the Securities and Exchange Commission SECC).Andersen, the smallest of the "big five" accounting firms, is now in deep trouble.
In the Middle Ages most synagogues had a genizah, because ceremonial burial (often with the remains of a pious, scholarly Jew) was thought to be the only fitting manner of disposing of sacred documents.
