An investigative journalist and author, Posner has written twelve books, including the New York Times bestsellers, Case Closed: Lee Harvey Oswald and the Assassination of JFK, which was a finalist for the Pulitzer in History, Why America Slept: The Failure to Prevent 9/11, and God's Bankers: A History of Money and Power at the Vatican. His wife, author Trisha Posner, works with him on all his projects.