NEW ORLEANS — Marie picked up the phone and dialed the number the detective gave her 10 days before, on the night she was raped at knifepoint outside a friend’s house in New Orleans. It was the first of many calls Marie would make in an 18-year ordeal of shoddy police work and numbingly slow prosecution to track down and convict her attacker. “Just checking to see if there are any leads, if you’ve caught anyone,” Marie recalls telling the detective. “Nothing’s turned up yet,” he responded.