Editor's note: Roland S. Martin is a syndicated columnist and author of "The First: President Barack Obama's Road to the White House." He is a commentator for the TV One cable network and host/managing editor of its Sunday morning news show, "Washington Watch with Roland Martin."
(CNN) -- There is no reason Marissa Alexander should spend the next 20 years in prison.
If you are the most hardened law-and-order person in the world, even you should have some compassion for Alexander, the Jacksonville, Florida, woman who has been struck by the ridiculous Florida law known as 10-20-life.
The law requires anyone convicted of an aggravated assault when a firearm is discharged to serve a minimum of 20 years in prison with no regard to extenuating circumstances.
Alexander says that on August 1, 2010, her husband went into a rage and tried to strangle her after reading some text messages she sent to her ex-husband. She fled the family home, got to the garage and realized she didn't have her keys. Fearing for her life, she says she grabbed a gun and went back into the home to retrieve her keys.
She says her husband threatened to kill her, and to keep him at bay, she fired a warning shot into a wall.
Why was she charged, convicted and sentenced? Because State Attorney Angela Corey, the same prosecutor leading the Trayvon Martin case, said the gun was fired near a bedroom where two children were and they could have been injured.
Did the bullet hit the children? No. Did Alexander point the gun at her husband and hit him? No. She simply fired a warning shot, and according to Florida's shameful law, that's enough for a minimum 20-year sentence.
Corey offered Alexander a three-year sentence in a plea bargain, but Alexander felt she had done nothing wrong and so rejected the plea.
In sentencing her, the judge made it clear that, despite all the pleas for mercy, including one from Alexander's 11-year-old daughter who took the stand, he was left with no choice but to send Alexander to jail for at least 20 years.
Alexander tried to invoke Florida's controversial stand your ground law in her defense, but that was rejected. Critics of the law's role in the Martin case have said this shows how the law is applied unevenly.
But the real issue here isn't the faulty stand your ground law. It's the ridiculous mandatory minimum sentences that have been approved by countless state legislatures and Congress.
In 2007, the U.S. Supreme Court ruled (PDF) that the federal sentencing guidelines in some types of cases should not be seen as mandatory but as "advisory," giving judges the leeway (PDF) to consider multiple factors before sentencing someone.
In a 2003 speech to the American Bar Association, Supreme Court Justice Anthony Kennedy railed against federal mandatory minimums, saying, "Our resources are misspent, our punishment too severe, our sentences too long."
"I can accept neither the necessity nor the wisdom of federal mandatory minimum sentences," Kennedy said. "In too many cases, mandatory minimum sentences are unwise or unjust."
Unfortunately, on the state level, far too many law-and-order legislators, most with no courtroom or law enforcement experience, enact such laws without giving any thought to potential cases like Alexander's.
The 10-20-life policy has no business in the laws of Florida or any other state.
Judges should have the discretion to consider a variety of factors in sentencing, and I have no doubt had this judge been given flexibility, Alexander wouldn't be going to prison for 20 years.
These types of injustices are common in our legal system, and it is necessary for everyone with a conscience to stand up and decry these so-called legislative remedies that end up as nightmares.
Alexander was a woman trying to flee an enraged husband. She could have easily pointed the gun at him and pleaded self-defense, and like George Zimmerman, the shooter in the Martin case who was not initially charged, Alexander might never have been arrested.
Our prison systems are overcrowded, and folks like Marissa Alexander do not belong in them.
One hopes that Florida Gov. Rick Scott will find some compassion and grant Alexander a pardon, and the Florida Legislature will revise the law to prevent future miscarriages of justice.
Florida elected officials and residents should be ashamed of this law and do all they can to change it.
The opinions expressed in this commentary are solely those of Roland S. Martin.