The Marissa Alexander case provides an excellent example of how an "imperfect" self-defense argument can have devastating and disproportionate consequences. Because the jury did not accept Ms. Alexander's self-defense argument, they had to convict. What they probably didn’t realize (because in Florida juries aren’t told the sentences attached to their verdicts) is that they triggered Florida’s 10-20-Life mandatory sentencing requirement.
In Florida, a person who uses a gun in the commission of certain felonies (including aggravated assault) must face minimum mandatory sentencing. If the gun is possessed during the commission of one of the enumerated felonies, a minimum 10-year sentence is required. If the gun was discharged, as it was in this case, it is 20 years. Florida’s minimum mandatory sentences are served day-per-day; there is no early release.
It might be appropriate to impose minimum mandatories on violent felons who use guns to further the commission of a crime such as armed robbery. The idea, however, that Florida does not allow any discretion--even judicial discretion--for more complicated scenarios truly makes it difficult to adjudicate these cases.