Aviation companies blame FBI, CIA and terrorists for 9/11

U.S. Attorney Michael Garcia said last year that the request for depositions with FBI agents was rejected because the aviation companies didn't explain how FBI information before the attacks would relate to their defense efforts.

Garcia said much of the information was protected from disclosure, "because it involves classified national security information or matters protected by the law enforcement investigative privilege."

He also said it would be "extremely difficult and burdensome" to separate the classified information from the non-classified information and risk that some classified materials may be inadvertently disclosed.

Yusill Scribner, a spokeswoman for government lawyers in the case, said there was no comment Wednesday.