Or is it? That’s been the question since Michael Peterson found his wife, Kathleen, at the bottom of a flight of stairs, or put her there, and launched a case that would serve as an autopsy of American justice. The story has surfaced and resurfaced for the better part of 20 years, but the latest version of “The Staircase” gets off to a rollicking start with that most engaging of plot devices-bloody murder.
