In this undated family photo, Trayvon Martin poses for a family photo. (AP Photo/HO, Martin Family Photos)   Here’s what we know: Trayvon Martin is dead.   On February 26, during halftime of the NBA All-Star game, the 17-year-old high school junior went to a nearby store in the Orlando suburb where he was visiting his father and stepmother in order to buy some candy for his younger brother. He returned to his family a six-foot, three-inch, 140-pound corpse.   We know who killed him.

George Zimmerman, a 28-year-old college student who had appointed himself captain of the neighborhood watch for the Retreat at Twin Lakes gated community, admits to shooting Martin with a 9mm handgun. Zimmerman spotted Martin and followed him in his car before placing a 911 call to report a “suspicious" person in the area.

“This guy looks like he’s up to no good, or he’s on drugs or something,” Zimmerman told the 911 operator. “He’s just staring, looking at all the houses.” What happened in the approximately twenty minutes between the time this call took place and when Zimmerman fired the shot that killed Martin is disputed—although recordings of the 911 call provide chilling hints—but what we do know is that Zimmerman claims he shot the young man in self-defense. This was enough for the police to let him go. Zimmerman was not and has, as of this writing, yet to be arrested.

We also know that Trayvon was black.

There are some who would argue that race is not a factor here. We’ve heard that Zimmerman is Hispanic—but this is not a defense. Neither is the statement released by Zimmerman’s father, which employs the “he has black friends” claim. Mentoring two black children and word from a black neighbor that she would entrust Zimmerman with her life doesn’t preclude him from holding racist views of black men. If it did, how then does he explain what made Martin a suspicious enough figure that it warranted Zimmerman leaving his vehicle and getting into an altercation with the young man?

What was the threat? We know that the only items retrieved from Martin’s person were a bag of Skittles, a can of iced tea, and some money, so unless Zimmerman felt he was in danger of contracting a deadly form of diabetes or a lethal cavity, he has more explaining to do. But whether the item is as innocuous as a bag of candy—or, as in Amadou Diallo’s case, a wallet—the assumption is that the natural state of black men is armed and dangerous.

If Martin was so threatening, why didn’t Zimmerman wait for the police to arrive, particularly after being told not to follow the suspect? (“We don’t need you to do that,” the dispatcher told him.) Why have three witnesses come forward to say that in the moments before the shooting they heard crying that stopped as soon as the bullet fired? Was Martin crying in anger? And what if he was? Would he not have a right to be angry that a man was stalking him for no reason? And if Martin was the aggressor, how did he manage to get a man over a hundred pounds heavier than himself to the ground? What injuries did Zimmerman sustain that would lead us to believe there was a struggle that left him in the grip of a life-and-death situation? The 911 tapes that have been released suggest that the two shots that were fired, one from a distance, the other the fatal one from close range. Does self-defense require a warning shot?

That these questions are likely to go unanswered in court of law is thanks to Florida’s “Stand Your Ground” law, which places the threshold for self-defense so low that you need little more than your word to show that your life was in danger. Zimmerman’s description of events was enough for the police, who evidently feel they know all that they need to know to determine that Zimmerman should be free to walk the streets while Martin’s family mourns. The crime of killing a black person still is not greater than the crime of being black. And, as one of the family’s attorneys asked, “Do we really believe that if Trayvon Martin had pulled the trigger, he would not have been arrested?”

We know that being a black man in America is a life-threatening occupation, whether you’re a 22-year-old in Oakland or a 13-year-old in Chicago or a 17 year-old in Orlando. The characters change, but the script remains the same. When everyone has had their say, another young black man has been killed for doing nothing more than being a young black man.

What we don’t yet know is what it will take to get justice for Trayvon.

A good place to start would be signing the Change.org petition started by his parents calling on Florida’s 18th District State’s Attorney to prosecute Zimmerman. Trayvon is dead, and black men everywhere live in constant fear they could be the next Trayvon. The very least we can do is put his killer in handcuffs.