Dep’t of Homeland Sec. v. MacLean, 574 U.S. ___, 135 S. Ct. 913 (2015)

Robert J. MacLean became a federal air marshal for the TSA in 2001. In that role, MacLean was assigned to protect passenger flights from potential hijackings. In July 2003, the Department of Homeland Security issued a confidential advisory about a potential hijacking plot by al Qaeda to be executed by