In 2003, the police arrested Al-Kidd as he was boarding a flight to Saudi Arabia, where he planned to study. He was held for 15 nights under the federal material witness statute (a law that allows police to hold people who are going to testify in court) because he was going to testify in the trial of Sami Omar Al-Hussayen. FBI Director Robert S. Mueller told Congress that al-Kidd's capture was one of the FBI's "success" stories. Al-Kidd was never charged with a crime or called as a witness. He was later released.