There was a time in the southern United States when racially charged murders of innocent civilians were routine. We remember the deaths of four little girls in the bombing of Birmingham’s 16th Street Baptist Church in September 1963; the June 1963 killing of Medgar Evers in Jackson, Miss.; and the murder of three young civil rights workers in June 1964 outside of Philadelphia, Miss.

But that was way back in the 20th century. Nobody could kill an innocent person today and get away with it. Right? Wrong! Add Trayvon Martin to the list.

This young black man was no civil rights activist. He was a 17-year-old high school junior, honor roll student, football player, hanging out with his father at his dad’s girlfriend’s house in Sanford, Fla. On the evening of Feb. 26, Trayvon went to a nearby 7-Eleven. After asking his little brother what he wanted, he hiked to the store and then began walking home, in the rain, wearing a hoodie, with nothing but a can of iced tea and a bag of Skittles for his brother. That’s when the ugliness of the Deep South rose again.

Martin was spotted by 28-year-old George Zimmerman, a white Hispanic Neighborhood Watch volunteer, who called police and reported someone acting “suspiciously.” Authorities promised to respond, after cautioning him not to pursue the young man, which was advice Zimmerman immediately ignored. Zimmerman got out of his car, pursued Martin, confronted him, shot and killed him – and then insisted he’d acted in self-defense.

And here’s the worst part: the Sanford Police Department swallowed his lame excuse – hook, line and sinker. They consider the case closed, they say, because they find no evidence to contradict Zimmerman’s claim of self-defense.

No evidence? How about this? Martin was walking and carrying only an iced tea and a bag of candy. Zimmerman was driving his car and armed with a 9 mm handgun. Martin weighed 140 pounds. Zimmerman weighs 250 pounds. Martin had no criminal record. Zimmerman was charged in July 2005 with resisting arrest with violence and battery on an officer. Plus, as reported in the Miami Herald, neighbors reported that Zimmerman was “fixated on crime and focused on young, black males.” He’d called police 46 times since January 2011 to report similar “suspicious activity.”

Zimmerman’s defense is further undermined by the testimony of Martin’s girlfriend, whom he called to tell he was being pursued by a stranger. She heard him ask Zimmerman “Why are you following me?” and urged him to run. Moments later, on one of several 911 calls neighbors made to police, Martin’s voice can be heard, crying for help.

Yet Sanford police did not arrest Zimmerman. They filed no charges against him. They didn’t even test him for drugs or alcohol. They performed a toxicology test on the dead teen, instead.

All evidence suggests this was nothing but cold-blooded murder by an overzealous vigilante, who confronted and killed Trayvon Martin only because he was black. But it’s also clear that no justice will be done as long as local cops are in charge. The U.S. Department of Justice is investigating whether Zimmerman should be charged with a civil rights crime. And the State Attorney’s Office has convened a grand jury in the case. But that’s not enough. Florida authorities should also take over the Sanford Police Department and demand the city manager fire its police chief.

Zimmerman should be placed on trial. But so also should Florida’s so-called “Stand Your Ground” statute, signed into law by Jeb Bush in 2005 and under which Zimmerman claims immunity. Many warned at the time it would encourage just this kind of mindless, violent behavior. And that’s exactly what’s happened. As reported by the Orlando Sentinel, there were 13 citizen killings in the five years before 2005, but 36 in the five years following. In 2009, there were 45. Trayvon Martin is the latest. It’s time to tighten the law, or repeal it.

It’s also time for President Obama to speak out about the injustice in this case. This could be a powerful teachable moment on how far we’ve come, yet how far we still have to go to achieve racial equality. And only he can deliver that message. As CNN’s Roland Martin reminded my radio audience, “If this had happened to a 17-year-old Barack Obama, he wouldn’t be sitting in the White House today.”

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