September 19, 2005: Able Danger Intelligence Officer Has Security Clearance Revoked

Lt. Col. Anthony Shaffer, an Army intelligence officer who worked closely with a military intelligence unit called Able Danger, has his security clearance revoked. [Government Executive, 9/21/2005; Times Herald (Norristown), 9/22/2005] Shaffer alleges that Able Danger identified Mohamed Atta and three other future 9/11 hijackers more than a year before the attacks (see August 17, 2005). Shaffer’s lawyer, Mark Zaid, states, “I specialize in security clearance cases.… Based on years of experience I can say categorically that the basis for the revocation was questionable at best.”
[US Congress, 9/21/2005] Shaffer is due to testify two days later in front of a Senate Judiciary Committee investigating Able Danger, though he is subsequently prohibited from doing so by the Defense Department (see September 21, 2005). His security clearance had been suspended 18 months previously (see March 2004).