Marissa Alexander, whose case brought allegations that Florida's Stand Your Ground law is being unfairly applied, was sentenced to 20 years in prison Friday after being convicted of three counts of aggravated assault after firing a warning shot during a dispute with her husband.

The case sparked a confrontation between a congresswoman and the prosecutor after the sentencing in Jacksonville, Fla., WJXT-TV reported.

Alexander, 31, claimed she fired a shot from a handgun into the wall to protect herself during a confrontation with her husband, who she said had abused her, WJXT reported. Two children were with him when she fired a shot in his direction, and she was charged with three counts of aggravated assault.

Her attorneys claimed self-defense and cited the state's Stand Your Ground law, which gives people some protection from prosecution for using potentially deadly force in cases in which they feel their life is threatened. The law came under nationwide scrutiny during the Trayvon Martin case, when neighborhood watch volunteer George Zimmerman shot an unarmed teen and authorities waited weeks before charging him.

theGrio: Allegations of abuse

But a jury agreed with prosecutors that the law didn't apply because she left during the argument, got a gun and returned to confront him, WJXT reported.

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Last week, State Attorney Angela Corey, who is also handling the Zimmerman case, said she personally met with Alexander and reviewed the evidence in the case, WJXT reported. She said she offered Alexander a three-year sentence before trial, despite the case qualifying for a 20-year minimum mandatory sentence.

The case has sparked rallies on Alexander's behalf, and WJXT described a heated scene outside the courtroom after the sentencing:

"Three years is not mercy and 20 years is not justice," U.S. Rep. Corrine Brown told Corey in an animated confrontation in the hallway. "If there ever was a stand-your-ground case, it was this one." ... She said she has been in contact with some of the best domestic violence attorneys in the country and will be involved in the appeals process. "This is the beginning, not the end," Brown said of Alexander case. "Clearly there is institutional racism."

At issue in the case were Alexander's actions leading up to the firing of the shot.

Alexander has said that 36-year-old Rico Gray had physically abused her in a dispute on Aug. 1, 2010. She testified that she fled into a garage and got a gun, but was unable to leave the home because the garage door was stuck. She testified that she went back into the house, where Gray was with his two sons, and fired the shot.

But Corey argued that Stand Your Law did not apply because Alexander acted in anger. The judge agreed, saying that by returning to the house, she showed she was not in fear for her life.

Gray had been arrested twice on domestic battery allegations, but Alexander had been charged with domestic battery four months after the shooting, Jacksonville.com reported.

The 20-year sentence was a mandatory minimum under Florida's "10-20-Life law," which mandates sentences for crimes involving a firearm, the Grio.com reported.

After the hearing, Alexander's attorney, Kevin Cobbin, said the Stand Your Ground law isn't always applied fairly, NBC station WLTV reported.

"The law was made for people like Ms. Alexander," Cobbin said. "They did not make it for people running around on the streets shooting people. They made it for women in their homes trying to defended themselves against abusive mean men."

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