In another e-mail exchange revealed during the investigation of disgraced lobbyist Jack Abramoff, a White House official was described as warning that "it is better to not put this stuff in writing in [the White House] . . . email system because it might actually limit what they can do to help us, especially since there could be lawsuits, etc." Abramoff responded in an e-mail that the message in question "was not supposed to go into the WH system."

So not only are we looking at missing documents, based on this comment we may be looking at something specifically used to avoid exposure of potentially illegal actions? This is nuts.

White House E-Mail Lost in Private Accounts - washingtonpost.com