On a rainy night five years ago, Officer Coleman "Duke" Brackney set off in pursuit of a suspected drunk driver, chasing his black Mazda Miata down rural Arkansas roads at speeds of nearly 100 miles per hour. When the sports car finally came to rest in a ditch, Brackney opened fire at the rear window and repeatedly struck the driver, 41-year-old James Ahern, in the back. The gunshots killed Ahern.

Prosecutors charged Brackney with felony manslaughter. But he eventually entered a plea to a lesser charge and could ultimately be left with no criminal record.

How the analysis was done: The 54 criminal prosecutions were identified by Bowling Green State University criminologist Philip M. Stinson and The Washington Post. Cases were culled from news reports, grand jury announcements and news releases from prosecutors. For individual cases, reporters obtained and reviewed thousands of pages of court records, police reports, grand jury indictments, witness testimony and video recordings. Dozens of prosecutors and defense attorneys in the cases were interviewed, along with legal experts, officers who were prosecuted and surviving relatives of the shooting victims.

Now, he serves as the police chief in a small community 20 miles from the scene of the shooting.