Florida's 'stand your ground' law in the gun again

Florida is facing renewed calls to reform its controversial "stand your ground" self-defence law after another jury failed to convict a white man of shooting dead an unarmed black teenager.

The judge in Jacksonville declared a mistrial after a jury said it was deadlocked on the murder charge against Michael Dunn, 47, who killed Jordan Davis, 17, after a row on a petrol station forecourt about blaring "thug music".

Dunn was still convicted of attempted murder and firing a deadly weapon. The case came just seven months after the similar Zimmerman murder trial in Florida.

The outcome prompted anger from demonstrators who marched through Jacksonville chanting "Justice for Jordan" after what they said was another case of lethal racial profiling of a black youth. "At what point do people begin to believe that 'stand your ground' becomes a licence to kill young black men with little provocation?" asked Jane Velez-Mitchell, a legal commentator.

Dunn fired 10 bullets in two bursts into a vehicle carrying the four black teenagers in November 2012. Like George Zimmerman, Dunn said he acted in fear of his life, arguing that he had the right to defend himself under the "stand your ground" law. The statute allows the use of deadly force in self-defence, with no need to retreat to avoid confrontation.

Davis' parents have campaigned for a change to the statute since their son's killing. "We will continue to wait for justice for Jordan," said his mother, Lucia McBath. The parents of Zimmerman's victim, Trayvon Martin, offered their support to Davis's family. "The killing is yet another reminder that, in Florida, racial profiling and stereotypes may serve as the basis for imaginary fear and the shooting and killing of young teenagers," said Tracy Martin and Sybrina Fulton.

Ken Jefferson, a vice-president for Operation Save Our Sons, a group that tries to help young men in Jacksonville, said: "There is a feeling of being able to shoot black people and get away with it."

There was also outrage that indications of Dunn's mindset were not put before the jury. "The jail is full of blacks and they all act like thugs," he wrote to his fiancee in letters released to the media. "If more people would arm themselves and kill these [expletive] idiots, when they're threatening you, eventually they may take the hint and change their behaviour."

Sixteen states have "stand your ground" statues. In 2012, a study by the Urban Institute, a Washington think-tank, found that the law had led to acquittals in 34 per cent of cases in which the gunman was white and the victim black - and in 3 per cent of cases when the position was reversed.