The killing of Trayvon Martin: Because he was black? IT TOOK a month or so, but the killing of Trayvon Martin, a teenager who was shot in Florida in late February, has developed into a predictable political circus. Barack Obama has opined on it, as have the Republicans hoping to wrest the presidency from him in November. Rush Limbaugh, a shrill right-wing radio host, has weighed in, and so has Al Sharpton, an equally excitable but ideologically opposite pundit-cum-activist. Mr Sharpton says he will "occupy" Sanford, the town where the shooting took place, until justice is done. An online petition calling for the arrest of the gunman, George Zimmerman, who is 28, has attracted over 2m signatures. The New Black Panther Party, a confrontational protest group, has offered $10,000 in exchange for a "citizen's arrest" of Mr Zimmerman. LeBron James, a basketball star, wrote "RIP Trayvon Martin" on his shoe before a game on March 23rd. He and other members of his team, the Miami Heat, also posed in hooded sweatshirts like the one Mr Martin was wearing when Mr Zimmerman decided to follow him, convinced he was "up to no good." The shooting took place in the gated community where Mr Zimmerman lives. He had recently started a neighbourhood-watch scheme and he frequently called the police to report everything from potholes to people he thought might be involved in a spate of burglaries. When he spotted Mr Martin while out driving on a rainy evening, he called the police from his car. The operator told him there was no need to follow Mr Martin, but Mr Zimmerman did so anyway. From that point, details are scant: the two men somehow got into a fight, during which Mr Zimmerman says his nose was broken, before he shot the unarmed 17-year-old. Mr Martin, it turns out, had been walking back to the house of his father's girlfriend in the gated community, having bought some sweets and iced tea at a nearby corner store. The local police did not arrest Mr Zimmerman, saying they had no evidence to dispute his claim that he had acted in self-defence. That decision prompted a cascade of protest, from other branches of government as well as the public. Sanford's city council passed a motion of no confidence in the city's chief of police, who is now suspended. The Justice Department announced it would conduct an investigation into the killing. Local prosecutors said they would convene a grand jury to consider the incident on April 10th. Florida is one of 20-odd states to have adopted a "stand your ground" law, which exempts those with reason to believe their lives are in jeopardy from any legal obligation to attempt to retreat before resorting to deadly force. Many have speculated that the police thought that the existence of the law would impede Mr Zimmerman's prosecution. Findings of justifiable homicide have tripled since the law took force in 2005. But Mr Zimmerman's lawyer says he does not intend to invoke the law if his client is arrested, while one of the law's authors says it would not apply in this case, anyway, as Mr Zimmerman seems to have gone out of his way to confront Mr Martin. Others have focused on the role of race in the killing. The National Association for the Advancement of Coloured People, for instance, has complained that the authorities neglected the case because Mr Martin was black. Many assume that Mr Zimmerman, whose father is white and whose mother is Hispanic, decided that Mr Martin looked suspicious simply because of the colour of his skin. Mr Obama seemed to allude to such a view when he said, "If I had a son, he would look like Trayvon." Rick Santorum and Newt Gingrich, two of the four remaining Republican presidential candidates, saw that as an opening, as did Mr Limbaugh. They declared themselves appalled that the president would view the shooting through the lens of race. From the left, Mr Obama has been criticised for not speaking loudly enough about the racial aspect of the killing. No incident is too tragic, it seems, for political point-scoring.