After Every Clue

Near the beginning of Cover-Up, the absorbing new documentary by Laura Poitras and Mark Obenhaus, there’s a shot of a Pentagon press briefing during the Vietnam War era. Still cameras click, movie cameras roll, and the auditorium’s seats are filled with reporters. Everyone is focused on the man at the podium, Defense Secretary Robert McNamara. The scene is a reminder that most journalists practice herd behavior. You write or broadcast what was said at the briefing, because if you don’t, your editor will berate you: “Hey, the rival newspaper [or rival network] just reported that McNamara said we’re winning the war. Why haven’t we heard that from you?” Whether covering City Hall or a state capital or the White House, every reporter worries about getting such a call. Yet in the end, the briefing is seldom the story that matters.