Late Saturday evening, George Zimmerman was found not guilty in the death of 17-year-old Trayvon Martin. The issue of self-defense played a central role in Zimmerman’s not guilty plea and his defense’s argument against the second-degree murder charges, and his acquittal is drawing comparisons in the media to the verdict of another high-profile Florida shooting incident: the case of Marissa Alexander. Alexander, an African-American Florida woman, was sentenced to 20 years in prison in 2012 for shooting what she described as warning shots into a wall during a confrontation with her husband. Alexander’s lawyers claimed self-defense in the case, and...