Criminal investigation

The Saudi Connection: Inside the 9/11 Case That Divided the F.B.I.

Washington’s efforts to keep secrets about possible Saudi connections to 9/11 have also intensified. Former F.B.I. agents who have made court statements in support of the 9/11 families have been warned by the bureau that they risk violating secrecy laws. Kenneth Williams — a retired agent who wrote a prescient memo before 9/11 about radical Arab students taking flying lessons in possible preparation for hijackings — said in a sworn declaration for the plaintiffs that an F.B.I. lawyer told him that the Trump administration did not want him to help them because it could imperil “good relations with Saudi Arabia.” (The F.B.I. declined to comment.)