The documents also show that the FBI helped facilitate interviews in the Philippines by California authorities investigating Jackson over allegations that he had sexually abused boys.
In 2004, the Santa Maria Police Department in California asked for FBI "involvement" after Jackson was arrested for child molestation.
Police, according to the FBI, said they believed the court case would be a "soft target" for terrorism because of the "worldwide media coverage" the trial would attract.
Jackson used Nation of Islam bodyguards during the legal proceedings.
The files say an FBI agent accompanied the California officials to the first interview to make sure there were no problems.
Jackson was acquitted of all 14 counts against him in what was one of the most widely followed cases in history.
The recording was of such poor quality that investigators appear to have been unable to determine what was on it. »
