by Cindy Loose and Pierre Thomas

About the author: Cindy Loose and Pierre Thomas are staff writers for the Washington Post.

Six-year-old Talonda Lanier, of Silver Spring, was curled up, sleeping, on the back seat of her mother’s car when a white Ford Escort passed. Six shots rang out, echoing off a concrete underpass on Interstate 40 in North Carolina. Talonda made a whining sound and in a small sleepy voice said, “Mommy.”

In the pre-dawn gloom, Saidat Lanier turned to comfort her daughter, saying, “It’s okay, baby.” A moment later, she glanced back again. Blood was streaming down the vinyl seat.

Talonda and the 16-year-old who passed by and shot at the car for no apparent reason suddenly had become part of what the Justice Department calls &ldquo...