The review found that Hasan, an Army psychiatrist, repeatedly failed to meet basic standards sets for officers for physical fitness, appearance and work ethic, but that superiors allowed his medical career to advance.

“Had those failings been properly adjudicated, he wouldn’t have progressed,” and could have been forced out of the armed services, said the official, speaking on condition of anonymity because the review’s findings had not been made public.

Instead, for much of Hasan’s career, supervisors were blinded by Hasan’s resume, the investigation found, believing they had found a rare medical officer: someone with a stellar undergraduate record, prior service in the infantry and intimate knowledge of the Islamic faith.

“The Army thought it had hit the trifecta,” said the official.