Executive Order 13233
When President Nixon resigned from office in 1974, forced out by the Watergate scandal, Congress enacted a law placing Nixon's presidential papers and records in federal custody to prevent them from being destroyed. Then, in 1978, Congress passed the Presidential Records Act, which gave the Archivist of the United States control over the records of former presidents and required that they be made public after a period of no more than 12 years.
In November 2001, George W. Bush issued EO 13233, entitled "Further Implementation of the Presidential Records Act." Under the provisions of this executive order, a sitting president can veto the release of a former president's records -- even if the former president has authorized the release of those records. Furthermore, the order requires that the public demonstrate a specific need for a document before it can be released.
Although the Bush administration has sought to justify EO 13323 on the grounds of protecting sensitive information related to national security, its decision to restrict access to the records of former presidents has generated significant opposition from journalists, historians, archivists, and other researchers.