Critics of mandatory-minimum sentencing laws are upset over a 20-year prison term imposed on a Florida woman for firing a warning shot to try to scare off her threatening husband.

Civil rights groups and other advocates say the sentencing of 31-year-old Marissa Alexander last week shows how stripping judges of discretion can result in unfair sentences. About two-thirds of the states have mandatory-minimum sentencing laws, usually for drug crimes.

Alexander tried unsuccessfully to invoke Florida's "stand your ground" law and rejected a plea deal for a lesser sentence after she was charged in a dispute with her husband. No one was hurt. A jury convicted her of aggravated battery with a firearm.

Florida's "10-20-life" law that targets gun crimes required the judge sentence her to 20 years.