"She (Sherry Sabol) denies advising that the agent (FBI Agent Steve Bongardt) could not participate in an interview and notes that she would not have given such inaccurate advice. The attorney (Sherry Sabol) told investigators that the NSA caveats would not have precluded criminal agents from joining in any search for Mihdhar... Moreover she (Sabol) said that she (FBI HQ Agent Dina Corsi) could have gone to the NSA and obtained a waiver of any such caveat because there was no FISA information involved in this case (the original reason for the NSA caveats)." This information was from testimony by NSLU attorney Sherry Sabol given to DOJ IG investigators on November 7, 2002
Verifying documentation: 9-11 Commission Report, Page 538, Footnote 81
See the book "Prior Knowledge of 9/11" for more in depth information on this.